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Kei Takasawa,1 Hiroyo Mabe,2 Fusa Nagamatsu,2 Naoko Amano,3 Yuichi Miyakawa,4 Akito Sutani,4 Reiko Kagawa,5 Satoshi Okada,5 Yusuke Tanahashi,6 Shigeru Suzuki,6 Shota Hiroshima,7 Keisuke Nagasaki,7 Sumito Dateki,8 Shigeru Takishima,9 Ikuko Takahashi,10 Kenichi Kashimada1 1Department of Pediatrics and Developmental Biology, Tokyo Medical and Dental University (TMDU), Tokyo, Japan; 2Department of Pediatrics, Kumamoto University Hospital, Kumamoto, Japan; 3Department of Pediatrics, Saitama City Hospital, Saitama, Japan; 4Department of Pediatrics, Kawaguchi Municipal Medical Center, Saitama, Japan; 5Department of Pediatrics, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan; 6Department of Pediatrics, Asahikawa Medical University, Asahikawa, Japan; 7Division of Pediatrics, Department of Homeostatic Regulation and Development, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan; 8Department of Pediatrics, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan; 9Department of Pediatrics, Soka Municipal Hospital, Saitama, Japan; 10Department of Pediatrics, Akita University Graduate School of Medicine, Akita, JapanCorrespondence: Kei Takasawa, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan, Tel +81-3-5803-5246, Fax +81-3-5803-5249, Email ktakasawa.ped@tmd.ac.jpIntroduction: Although the treatment success of long-term growth hormone therapy (GHT) is dependent on maintaining patients’ adherence to treatment, marked variations in adherence levels among children with GHT (eg, 7– 71% nonadherence) have been reported. Barriers to or promoters of GHT adherence have been discussed and investigated, and digital health technologies, such as electronic GH injection devices, may have the potential to assess adherence to GHT more accurately. Thus, we conducted a multicenter, retrospective cohort study using GH injection log analysis of an electronic GH device, GROWJECTOR®L, to qualify adherence and explore the factors influencing adherence.Methods: This study enrolled 41 patients (median[range] age, 5.8[3.0 ~ 17.0] years) with short stature from nine Japanese medical institutions. The injection log data (12– 48 weeks) were read by smartphones and collected into the data center through a cloud server.Results: Although cumulative adherence rates remained higher than 95% throughout the observation period, five (12.2%) patients had low adherence (< 85%). Subsequently, subgroup and logistic regression analyses for exploring factors affecting adherence revealed that self-selection of GH device and irregular injection schedule (ie, frequent injections after midnight) significantly affected adherence rate (p=0.034 and 0.048, respectively). In addition, higher rates of irregular injections significantly affected low adherence (median[range], 11.26[0.79 ~ 30.50]% vs 0.26[0.00 ~ 33.33]%, p = 0.029).Discussion: Our study indicated that injection log analysis using an electronic GH device could detect irregular injection schedules due to a night owl or disturbance in lifetime rhythm affecting low adherence and had significant potential to encourage collaborative monitoring of adherence with healthcare providers and patients themselves/caregivers, along with growing autonomy and shared decision-making. Our study suggests the significance of narrative and personal approaches to adherence of patients with GHT and the usefulness of digital devices for such an approach and for removing various barriers to patient autonomy, leading to improvement and maintenance of adherence.Keywords: GH therapy, digital health technology, shared decision- making, patient autonomy

Citrin deficiency is an autosomal recessive disorder caused by a defect of citrin resulting from mutations in the SLC25A13 gene. Intrahepatic cholestasis and various metabolic abnormalities, including hypoglycemia, galactosemia, citrullinemia, and hyperammonemia may be present in neonates or infants in the "neonatal intrahepatic cholestasis caused by citrin deficiency" (NICCD) form of the disease. Because at present, newborn screening (NBS) for citrin deficiency using citrulline levels in dried blood spots (DBS) can only detect some of the patients, we tried to develop a new evaluation system to more reliably detect newborns with citrin deficiency utilizing parameters already in place in present NBS methods. To achieve this goal, we re-analyzed NBS profiles of amino acids and acylcarnitines in 96 NICCD patients, who were diagnosed through selective screening or positive family history. Hereby, we identified the combined evaluation of arginine (Arg), citrulline (Cit), isoleucine+leucine (Ile + Leu), tyrosine (Tyr), free carnitine (C0) / glutarylcarnitine (C5-DC) ratio in DBS as potentially sensitive to diagnose citrin deficiency in pre-symptomatic newborns. In particular, a scoring system using threshold levels for Arg (≥9 μmol/L), Cit (≥ 39 μmol/L), Ile + Leu (≥ 99 μmol/L), Tyr (≥ 96 μmol/L) and C0/C5-DC ratio (≥327) was significantly effective to detect newborns who later developed NICCD, and could thus be implemented in existing NBS programs at no extra analytical costs whenever citrin deficiency is considered to become a novel target disease., (© 2023 SSIEM.)

Context: Defects in MKRN3, DLK1, KISS1, and KISS1R and some disorders, such as Temple syndrome (TS14), cause central precocious puberty (CPP). Recently, pathogenic variants (PVs) in MECP2 have been reported to be associated with CPP., Objective: We aimed to clarify the contribution of (epi)genetic abnormalities to CPP and clinical and hormonal features in each etiology., Subjects and Methods: We conducted targeted sequencing for MKRN3, DLK1, MECP2, KISS1, and KISS1R and methylation analysis for screening of imprinting disorders such as TS14 associated with CPP in 90 patients with CPP (no history of brain injuries and negative brain MRI) and collected their clinical and laboratory data. We measured serum DLK1 levels in three patients with TS14 and serum MKRN3 levels in two patients with MKRN3 genetic defects, together with some etiology-unknown patients with CPP and controls., Results: We detected eight patients with TS14 (six, epimutation; one, mosaic maternal uniparental disomy chromosome 14; one, microdeletion) and three patients with MKRN3 genetic defects (one, PV; one, 13-bp deletion in the 5'-untranslated region (5'-UTR); one, microdeletion) with family histories of paternal early puberty. There were no patients with PVs identified in MECP2, KISS1, or KISS1R. We confirmed low serum MKRN3 level in the patient with a deletion in 5'-UTR. The median height at initial evaluation of TS14 patients was lower than that of all patients. Six patients with TS14 were born small for gestational age (SGA)., Conclusion: (Epi)genetic causes were identified in 12.2% of patients with CPP at our center. For patients with CPP born SGA or together with family histories of paternal early puberty, (epi)genetic testing for TS14 and MKRN3 genetic defects should be considered. (271/250)., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com. See the journal About page for additional terms.)

TSC2/PKD1 contiguous gene syndrome is caused by deletions involving the TSC2 and PKD1 genes that lead to tuberous sclerosis complex and autosomal dominant polycystic kidney disease. It is characterized by early-onset severe cystic kidney disease with progressive enlargement of the kidneys and the cysts. As it can lead to early hypertension and an accelerated decline of kidney function, early genetic testing is needed for early diagnosis of this syndrome, and more frequent imaging-based examinations are necessary to assess disease progression and determine appropriate management. We report the case of an infant girl with TSC2/PKD1 contiguous gene syndrome who presented with epileptic seizures. Brain magnetic resonance imaging (MRI) revealed subependymal nodules and cortical tubers, and abdominal MRI revealed polycystic kidney lesions and enlargement of both kidneys. TSC2/PKD1 contiguous gene syndrome was suspected from her radiological features, and we confirmed the presence of a deletion in the girl's genome, which included the TSC2 and PKD1 genes, via microarray analysis. Thereafter, we evaluated the change in kidney size via repeated abdominal MRI. The polycystic kidney lesions enlarged, and the patient developed hypertension in early childhood, for which we administered an angiotensin-converting enzyme inhibitor. We emphasize the importance of evaluation with longitudinal abdominal imaging because renal cysts tend to enlarge rapidly and induce hypertension, as demonstrated in our case., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Hashimoto et al.)

Achondroplasia (ACH) is a rare, autosomal dominant skeletal dysplasia characterized by short stature, characteristic facial configuration, and trident hands. Before vosoritide approval in Japan, patients with ACH could start growth hormone (GH) treatment at age 3 years. However, ACH and its treatment in young Japanese children have not been studied. This retrospective, longitudinal, medical records-based cohort study (before vosoritide approval) summarized symptoms, complications, monitoring, surgery/interventions, and height with/without GH in Japanese patients with ACH <5 years. Complications were observed in 89.2% of all 37 patients; 75.7% required surgery or intervention. All patients were monitored by magnetic resonance imaging; 73.0% had foramen magnum stenosis, while 54.1% had Achondroplasia Foramen Magnum Score 3 or 4. Of 28 GH-treated patients, 22 initiating at age 3 years were generally taller after 12 months versus 9 non-GH-treated patients. Mean annual growth velocity significantly increased from age 2 to 3 versus 3 to 4 years in GH-treated patients (4.37 vs. 7.23 cm/year; p = 0.0014), but not in non-GH-treated patients (4.94 vs. 4.20 cm/year). The mean height at age 4 years with/without GH was 83.6/79.8 cm. These results improve our understanding of young patients with ACH in Japan and confirm that early diagnosis of ACH and monitoring of complications help facilitate appropriate interventions., (© 2024 The Authors. American Journal of Medical Genetics Part A published by Wiley Periodicals LLC.)

A 24-year-old man was admitted to our hospital because of severe heart failure. Although he was treated with diuretics and positive inotropic agents, his heart failure progressed. An endomyocardial biopsy revealed iron deposition in his myocytes. Finally, he was diagnosed with hereditary hemochromatosis. After starting administration of an iron-chelating agent in addition to conventional treatment for heart failure, his condition improved. We should consider hemochromatosis in heart failure patients with severe right ventricular dysfunction in addition to left ventricular dysfunction.

Objective: Pseudohypoparathyroidism type 1B (PHP1B) caused by methylation defects of differentially methylated regions (DMRs) on the GNAS locus can be categorized into groups according to etiologies and methylation defect patterns of the DMRs. The aim of this study was to clarify the clinical characteristics of each group., Design: Comprehensive molecular analyses consisting of methylation, copy number, and microsatellite analyses., Methods: Eighty-four patients with PHP1B were included in this study. We classified them into 5 groups, namely, autosomal dominant inheritance-PHP1B (Group 1, G1), sporadic-PHP1B (G2), and atypical-PHP1B (G3-G5), based on the methylation defect patterns in 4 DMRs on the GNAS locus and etiologies and evaluated the clinical findings in each group and compared them among the groups., Results: G2 had the youngest age and the highest serum intact parathyroid hormone levels among the 5 groups at the time of diagnosis. The most common symptoms at the time of diagnosis were tetany in G1, and seizures or loss of consciousness in G2. Albright's hereditary osteodystrophy and PHP-suggestive features were most frequently observed in the G2 proband. Nine patients had neurodevelopmental disorders (NDs) consisting of mild to borderline intellectual disability and/or developmental delay. There were no significant correlations between the average methylation ratios of 7 CpG sites in the GNAS-A/B:TSS-DMR and hormonal and biochemical findings., Conclusion: This study revealed the differences in some clinical characteristics, particularly clinical features, and ages at the time of diagnosis between G2 and other groups and detailed NDs observed in some patients with PHP1B., Competing Interests: Conflict of interest: The authors report no conflicts of interest., (© The Author(s) 2023. Published by Oxford University Press on behalf of European Society of Endocrinology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Congenital anomalies of the kidney and urinary tract (CAKUT) represent the most common cause of chronic kidney failure in children. Despite growing knowledge of the genetic causes of CAKUT, the majority of cases remain etiologically unsolved. Genetic alterations in roundabout guidance receptor 1 (ROBO1) have been associated with neuronal and cardiac developmental defects in living individuals. Although Slit-Robo signaling is pivotal for kidney development, diagnostic ROBO1 variants have not been reported in viable CAKUT to date. By next-generation-sequencing methods, we identified six unrelated individuals and two non-viable fetuses with biallelic truncating or combined missense and truncating variants in ROBO1. Kidney and genitourinary manifestation included unilateral or bilateral kidney agenesis, vesicoureteral junction obstruction, vesicoureteral reflux, posterior urethral valve, genital malformation, and increased kidney echogenicity. Further clinical characteristics were remarkably heterogeneous, including neurodevelopmental defects, intellectual impairment, cerebral malformations, eye anomalies, and cardiac defects. By in silico analysis, we determined the functional significance of identified missense variants and observed absence of kidney ROBO1 expression in both human and murine mutant tissues. While its expression in multiple tissues may explain heterogeneous organ involvement, variability of the kidney disease suggests gene dosage effects due to a combination of null alleles with mild hypomorphic alleles. Thus, comprehensive genetic analysis in CAKUT should include ROBO1 as a new cause of recessively inherited disease. Hence, in patients with already established ROBO1-associated cardiac or neuronal disorders, screening for kidney involvement is indicated., (Copyright © 2022 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)

A 5-month-old boy was referred to our department to examine poor development of external genitalia. The patient was diagnosed with micropenis and bilateral impalpable testes, and testosterone replacement therapy was recommended. The testes remained impalpable at 14 months of age; therefore, laparoscopy was performed to explore intra-abdominal testes. The patient was incidentally diagnosed with congenital unilateral absence of the right vas deferens. A renal sonography performed after the operation revealed a high possibility of right renal agenesis. Congenital absence of the vas deferens is associated with a high probability of renal anomalies. It is, therefore, essential to pay careful attention to renal dysfunction.

Sitosterolemia is caused by homozygous or compound heterozygous gene mutations in either ATP-binding cassette subfamily G member 5 (ABCG5) or 8 (ABCG8). Since ABCG5 and ABCG8 play pivotal roles in the excretion of neutral sterols into feces and bile, patients with sitosterolemia present elevated levels of serum plant sterols and in some cases also hypercholesterolemia. A 48-year-old woman was referred to our hospital for hypercholesterolemia. She had been misdiagnosed with familial hypercholesterolemia at the age of 20 and her serum low-density lipoprotein cholesterol (LDL-C) levels had remained about 200-300 mg/dL at the former clinic. Although the treatment of hydroxymethylglutaryl-CoA (HMG-CoA) reductase inhibitors was ineffective, her serum LDL-C levels were normalized by ezetimibe, a cholesterol transporter inhibitor. We noticed that her serum sitosterol and campesterol levels were relatively high. Targeted analysis sequencing identified a novel heterozygous ABCG5 variant (c.203A>T; p.Ile68Asn) in the patient, whereas no mutations were found in low-density lipoprotein receptor (LDLR), proprotein convertase subtilisin/kexin type 9 (PCSK9), or Niemann-Pick C1-like intracellular cholesterol transporter 1 (NPC1L1). While sitosterolemia is a rare disease, a recent study has reported that the incidence of loss-of-function mutation in the ABCG5 or ABCG8 gene is higher than we thought at 1 in 220 individuals. The present case suggests that serum plant sterol levels should be examined and ezetimibe treatment should be considered in patients with hypercholesterolemia who are resistant to HMG-CoA reductase inhibitors.

Sitosterolemia is an autosomal recessive disorder that affects lipid metabolism and is characterized by elevated serum plant sterol levels, xanthomas, and accelerated atherosclerosis. In this study, we report a novel nonsense single-nucleotide variant, c.225G > A (p.Trp75*), and an East Asian population-specific missense multiple-nucleotide variant, c.1256&#95;1257delTCinsAA (p.Ile419Lys), in the ABCG8 gene in a compound heterozygous state observed in a Japanese girl with sitosterolemia., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© The Author(s) 2020.)

Objectives Imprinted genes have important roles for normal growth and development. Imprinting disorders (IDs) such as Silver-Russell syndrome and Temple syndrome are rare diseases that typically cause short children born small for gestational age (SGA). However, some patients with short stature (SS) caused by IDs were born non-SGA. To date, the contribution of IDs to idiopathic short stature (ISS) has been poorly investigated. The aim of this study was to clarify the contribution of IDs to ISS. Methods We conducted methylation analysis for 10 differentially methylated regions using pyrosequencing to detect known IDs in 58 patients (31 male and 27 female children, height standard deviation score -4.2 to -2.0) carrying a clinical diagnosis of ISS. Results We identified no patient with IDs among these patients with ISS. Conclusions These results indicate that IDs are rare in patients having ISS, and that imprinted genes affect fetal growth more than postnatal growth. Because patients with IDs born non-SGA usually have clinical features characteristic of each ID, in addition to SS, the patients with ISS as a clinical diagnosis may not be associated with IDs. It is unlikely that cases clinically diagnosed with ISS are caused by IDs leading to growth failure.

Background Denosumab is an inhibitor of receptor activator of nuclear factor kappa-B ligand, which strongly suppresses osteoclasts. Cherubism is a rare autosomal dominant disorder characterized by symmetrical swelling of the jaws, in which the bone is replaced by a fibrous granuloma containing osteoclast-like giant cells. Case presentation We report the efficacy and safety of denosumab treatment in a prepubertal boy with progressive cherubism. The treatment consisting of eight subcutaneous denosumab injections (120 mg/dose) in 6 months not only suppressed the expansion of the osteolytic lesions but also dramatically ossified them. However, a transiently decreased growth rate and rebounded asymptomatic hypercalcemia were associated with the treatment. Conclusions The present case demonstrated the therapeutic potential of denosumab for treatment of cherubism, although adverse effects, especially those on childhood growth, remain obscure. Further studies are needed to establish a safe and effective protocol for denosumab treatment of children.

Heterozygous pathogenic variants in the KAT6B gene, which encodes lysine acetyltransferase 6B, have been identified in patients with congenital rare disorders, including genitopatellar syndrome and Say-Barber-Biesecker-Young-Simpson syndrome. Herein, we report another Japanese patient with a KAT6B -related disorder and a novel de novo heterozygous variant in exon 18 of KAT6B [c.3925dup, p.(Glu1309fs*33)], providing further evidence that truncating variants in exon 17 and in the proximal region of exon 18 are associated with genitopatellar syndrome-like phenotypes., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© The Author(s) 2019.)

Coffin-Siris syndrome (CSS, MIM#135900) is a congenital disorder characterized by coarse facial features, intellectual disability, and hypoplasia of the fifth digit and nails. Pathogenic variants for CSS have been found in genes encoding proteins in the BAF (BRG1-associated factor) chromatin-remodeling complex. To date, more than 150 CSS patients with pathogenic variants in nine BAF-related genes have been reported. We previously reported 71 patients of whom 39 had pathogenic variants. Since then, we have recruited an additional 182 CSS-suspected patients. We performed comprehensive genetic analysis on these 182 patients and on the previously unresolved 32 patients, targeting pathogenic single nucleotide variants, short insertions/deletions and copy number variations (CNVs). We confirmed 78 pathogenic variations in 78 patients. Pathogenic variations in ARID1B, SMARCB1, SMARCA4, ARID1A, SOX11, SMARCE1, and PHF6 were identified in 48, 8, 7, 6, 4, 1, and 1 patients, respectively. In addition, we found three CNVs including SMARCA2. Of particular note, we found a partial deletion of SMARCB1 in one CSS patient and we thoroughly investigated the resulting abnormal transcripts.

Spondylocarpotarsal synostosis syndrome, a rare syndromic skeletal disorder characterized by disrupted vertebral segmentation with vertebral fusion, scoliosis, short stature, and carpal/tarsal synostosis, has been associated with biallelic truncating mutations in the filamin B gene or monoallelic mutations in the myosin heavy chain 3 gene. We herein report the case of a patient with a typical phenotype of spondylocarpotarsal synostosis syndrome who had a homozygous frameshift mutation in the refilin A gene (RFLNA) [c.241delC, p.(Leu81Cysfs*111)], which encodes one of the filamin-binding proteins. Refilins, filamins, and myosins play critical roles in forming perinuclear actin caps, which change the nuclear morphology during cell migration and differentiation. The present study implies that RFLNA is an additional causative gene for spondylocarpotarsal synostosis syndrome in humans and a defect in forming actin bundles and perinuclear actin caps may be a critical mechanism for the development of spondylocarpotarsal synostosis syndrome.

The genetic causes of combined pituitary hormone deficiency remain elusive in most patients. Recently, incompletely penetrant heterozygous mutations in ROBO1 have been described in patients with pituitary stalk interruption syndrome. Herein, we identified a novel homozygous slice site mutation in ROBO1 (c.1342+1G>A) using a trio whole-exome sequencing strategy in a 5-year-old Japanese boy who had combined pituitary hormone deficiency, psychomotor developmental delay, severe intellectual disability, sensorineural hearing loss, strabismus, and characteristic facial features, including a broad forehead, micrognathia, and arched eyebrows. Magnetic resonance imaging delineated anterior pituitary hypoplasia, ectopic posterior pituitary, invisible pituitary stalk, thinning of the corpus callosum, and hypoplasia of the pons and midbrain. The phenotypically normal parents (first cousins) were heterozygous for the mutation. The results provide further evidence of ROBO1 being involved in the development of the pituitary gland. A recessive mutation of ROBO1 is a potential novel cause of a syndromic disorder associated with combined pituitary hormone deficiency.

Pseudohypoparathyroidism type 1A (PHP1A) is characterized by resistance to multiple hormones, the Albright Hereditary Osteodystrophy phenotype, obesity, and developmental delay. Developmental delay usually appears prior to hypocalcemia due to parathyroid hormone resistance and could be a clinically important feature for early diagnosis of PHP1A. To date, however, the details have not been documented. With regard to developmental delays, we conducted a multicenter retrospective study of 22 PHP1A patients from 18 families who were diagnosed clinically or genetically from 2005 to 2015. For quantitative analysis of their development, we calculated the ratios of the milestone ages of the patients to those in normal reference data. The ratio of the ages with respect to speech development, i.e., speaking a first meaningful word (median: 1.67), was significantly higher than that for gross motor development, walking unassisted (median: 1.34). The ratio of age at stringing a two-word sentence (median: 1.32) was significantly lower than that of saying a first word (median: 1.84). Ten out of 11 (91%) patients exhibited two or three of the following clinical phenotypes: developmental delay, obesity, and hyperthyrotropinemia. These results suggest two possible clinical features of developmental delays in PHP1A patients: developmental delay is more obvious in speech acquisition than in gross motor skills, and speech delays could be attenuated during later childhood. Further, the presence of multiple of three clinical symptoms could be an important indicator to differentiate the diagnosis of PHP1A during early childhood.

Background: Type A insulin resistance (IR) is a rare form of severe congenital IR that is frequently caused by heterozygous mutations in the insulin receptor (INSR) gene. Although Type A IR requires appropriate intervention from the early stages of diabetes, proper diagnosis of this disease is challenging, and accumulation of cases with detailed clinical profiles and genotypes is required., Methods: Herein we report on six peripubertal patients with clinically diagnosed Type A IR, including four patients with an identified INSR mutation. To clarify the clinical features of Type A IR due to INSR mutation, we validated the clinical characteristics of Type A IR patients with identified INSR mutations by comparing them with mutation-negative patients., Results: Four heterozygous missense mutations within the β-subunit of INSR were detected: Gly1146Arg, Arg1158Trp, Arg1201Trp, and one novel Arg1201Pro mutation. There were no obvious differences in clinical phenotypes, except for normal lipid metabolism and autosomal dominant inheritance, between Type A IR due to INSR mutations and Type A IR due to other factors. However, our analysis revealed that the extent of growth retardation during the fetal period is correlated with the severity of insulin signaling impairment., Conclusions: The present study details the clinical features of four patients with genetically proven Type A IR. Further accumulation of genetically proven cases and long-term treatment prognoses following early diagnosis are required to further elucidate the dynamics of this disease., (© 2018 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.)

Glioblastoma 2 (GLI2) is a mediator of Sonic hedgehog signaling pathway that plays an important role in development of the central nervous system and limbs. Heterozygous GLI2 mutations have been associated with postaxial polydactyly, various pituitary dysfunction, and holoprosencephaly-like phenotype. Herein, we report a Japanese boy who presented with isolated growth hormone deficiency with ectopic posterior pituitary, postaxial polydactyly, atrioventricular septal defect, intellectual disability and dysmorphic facial features including mid-facial hypoplasia. The patient was also complicated with congenital urethral stricture with megacystis, hydronephrosis, and renal hypoplasia/dysplasia, which led to end-stage renal failure by the age of 8 years. Trio-whole-exome sequencing showed a novel de novo heterozygous frameshift mutation in GLI2 (c.3369delG, p.Met1123Ilefs*7) in the patient. This is the first report of possible association between GLI2 mutation and the phenotype of congenital anomalies of the kidney and urinary tract, and subsequent end-stage renal failure. Further studies on the urogenital phenotype in patients with GLI2 mutations may clarify a role of GLI2 in embryonic development of the urinary tract.

The LARP7 gene encodes a chaperone protein of the noncoding RNA 75 K, and mutations in this gene have been identified in patients with Alazami syndrome. Herein, we report another Japanese patient with Alazami syndrome and novel compound heterozygous variants in LARP7 (i.e., c.370delG, p.Glu124fs*38 and c.641&#95;667+25del involving the splice donor site of intron 8). These findings provide further evidence that biallelic LARP7 defects cause the phenotype of Alazami syndrome., Competing Interests: The authors declare no conflict of interest.

Takenouchi-Kosaki syndrome (TKS) is a congenital malformation syndrome characterized by severe developmental delay, macrothrombocytopenia, camptodactyly, sensorineural hearing loss, and dysmorphic facial features. Recently, a heterozygous de novo mutation (p.Tyr64Cys) in the CDC42 gene, which encodes a key small GTP-binding protein of the Rho-subfamily, was identified in two unrelated patients with TKS. We herein report a third patient with TKS who had the same heterozygous CDC42 mutation. The phenotype of the patient was very similar to those of the two previously reported patients with TKS; however, she also demonstrated novel clinical manifestations, such as congenital hypothyroidism and immunological disturbance. Thus, despite the heterozygous mutation of CDC42 (p.Tyr64Cys) likely being a hot-spot mutation for TKS, its phenotype may be variable. Further studies and the accumulation of patients with CDC42 mutations are needed to clarify the phenotype in patients with TKS and the pathophysiological roles of the CDC42 mutation.

Background: There are few reports pertaining to Asian patients with neonatal diabetes mellitus (NDM) caused by activating mutations in the ATP-sensitive potassium channel genes (KATP-NDM)., Objectives: To elucidate the characteristics of Japanese patients with KATP-NDM., Methods: By the amplification and direct sequencing of all exons and exon-intron boundaries of the KCNJ11 and ABCC8 genes, 25 patients with KATP-NDM were identified from a total of 70 patients with NDM. Clinical data were collected from the medical charts., Results: Sixteen patients had mutations in KCNJ11 and nine in ABCC8. Eight novel mutations were identified; two in KCNJ11 (V64M, R201G) and six in ABCC8 (R216C, G832C, F1176L, A1263V, I196N, T229N). Interestingly, V64M caused DEND (developmental delay, epilepsy, neonatal diabetes) syndrome in our patient, while mutation of the same residue (V64G) had been reported to cause congenital hyperinsulinism. Mutations in ABCC8 were associated with TNDM (4/9) or isolated PNDM (5/9), whereas those in KCNJ11 were associated with more severe phenotypes, including DEND (3/16), iDEND (intermediate DEND, 4/16), or isolated PNDM (6/16). Switching from insulin to glibenclamide monotherapy was successful in 87.5% of the patients. Neurological improvement was observed in two patients, one with DEND (T293N) and one with iDEND (R50P) syndrome. Three others with iDEND mutations (R201C, G53D, and V59M) remained neurologically normal at 5, 1, and 4 years of age, respectively, with early introduction of sulfonylurea., Conclusion: Overall, clinical presentation of KATP-NDM in Japanese patients was similar to those of other populations. Early introduction of sulfonylurea appeared beneficial in ameliorating neurological symptoms., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Although mutations in ACAN, FGFR3, NPR2, and SHOX typically lead to skeletal dysplasia, and mutations in GHRHR, GH1, GHR, STAT5B, IGF1, IGFALS, and IGF1R usually underlie hormonal defects of the growth hormone (GH)-insulin-like growth factor 1 (IGF1) axis, such mutations have also been identified in patients with idiopathic short stature (ISS). Of these, SHOX abnormalities are known to account for a certain percentage of ISS cases, whereas the frequency of mutations in the other 10 genes in ISS cohorts remains unknown. Here, we performed next-generation sequencing-based mutation screening of the 10 genes in 86 unrelated Japanese ISS patients without SHOX abnormalities. We searched for rare protein-altering variants. The functional significance of the identified variants was assessed by in silico analyses. Consequently, we identified 18 heterozygous rare variants in 19 patients, including four probable damaging variants in ACAN, six pathogenicity-unknown variants in FGFR3, GHRHR, GHR, and IGFALS, and eight possible benign variants. Pathogenic variants in NPR2, GH1, and IGF1 were absent from our cohort. Unlike previously reported patients with ACAN mutations, our four patients with ACAN variants manifested non-specific short stature with age-appropriate or mildly delayed bone ages, and had parents of normal stature. These results indicate that ACAN mutations can underlie ISS without characteristic skeletal features, and that such mutations are possibly associated with de novo occurrence or low penetrance. In addition, our data imply that mutations in FGFR3, NPR2, and GH-IGF1 axis genes play only limited roles in the etiology of ISS.

Silver-Russell syndrome (SRS) is a congenital developmental disorder characterized by intrauterine and postnatal growth failure, craniofacial features (including a triangular shaped face and broad forehead), relative macrocephaly, protruding forehead, body asymmetry and feeding difficulties. Hypomethylation of the H19 differentially methylated region (DMR) on chromosome 11p15.5 is the most common cause of the SRS phenotype. We report the first SRS patient with hypomethylation of the H19-DMR and maternally derived 15q11.2-q13.1 duplication. Although her clinical manifestations overlapped with those of previously reported SRS cases, the patient's intellectual disability and facial dysmorphic features were inconsistent with the SRS phenotype. Methylation analyses, array comparative genomic hybridization, and a FISH analysis revealed the hypomethylation of the H19-DMR and a maternally derived interstitial 5.7 Mb duplication at 15q11.2-q13.1 encompassing the Prader-Willi/Angelman critical region in the patient. On the basis of the genetic and clinical findings in the present and previously reported cases, it is unlikely that the 15q duplication in the patient led to the development of hypomethylation of the H19-DMR and it is reasonable to consider that the characteristic phenotype in the patient was caused by the coexistence of the two (epi)genetic conditions. Further studies are needed to clarify the mechanisms leading to methylation aberrations in SRS.

Aggrecan is a critical proteoglycan component of the extracellular matrix of the growth plates and articular cartilage and has a key role in the biophysical and biomechanical properties of cartilage. Recently, heterozygous mutations in the ACAN gene, which encodes aggrecan, have been identified in patients with short stature and accelerated bone age. We herein report another family with a heterozygous ACAN mutation associated with idiopathic short stature along with accelerated bone age and early-onset herniation of the lumbar discs at the levels of L1/2 through L5/S1. Whole-exome sequencing identified a novel heterozygous frameshift mutation in the ACAN gene (c.1744delT; p.Phe582fs*69) in all of the affected family members but not in the unaffected one, providing further evidence that ACAN haploinsufficiency causes short stature with advanced bone maturation. In addition, we advocate early-onset multiple disc herniation as a novel phenotype associated with ACAN haploinsufficiency.

Arterial spin labeling (ASL) is a magnetic resonance imaging (MRI) technique that enables visualizing of cerebral blood flow without need of a contrast medium. In recent years, there have been reports from outside Japan related to ASL use in migraine attacks. We report two cases of acute confusional migraine (ACM) in children. At time of confusion, ASL imaging showed reduced blood flow: for the first patient, in both cerebral hemispheres from the occipital lobe through the parietal lobe to the temporal lobe; for the second patient, throughout the left cerebral hemisphere. T1-, T2-, diffusion-weighted images, and fluid attenuation inversion recovery (FLAIR) images indicated normal results. Subsequent ASL re-examinations for both cases showed recovery from reduced blood flow. In our view, ACM can be characterized by a reduction in blood flow not limited to the occipital lobe but across wide regions of the cerebral hemisphere. We consider ASL to be helpful in the difficult differentiation of ACM from other disturbances of consciousness, in addition to enabling repeated examinations without the risks associated with single-photon emission computed tomography (SPECT) concerning radiation exposure or with contrast MRI concerning contrast media use.

We herein report a de novo hemizygous 9.2-Mb interstitial deletion of chromosome 11p14.1-15.3 in a 3-year-old Japanese girl with short stature, relative macrocephaly, and delayed closure of cranial fontanelles and sutures. She did not show either any motor or mental development delay. This deletion involves 25 genes including NELL1. The loss of the Nell1 function leads to skeletal defects in the cranial vault and vertebral column, and overexpression of Nell1 causes craniosynostosis in mice. These results imply that short stature and an abnormality of membranous ossification could be explained by haploinsufficiency of NELL1 on 11p14.1-p15.3. Further studies are needed to clarify the phenotype in patients with an 11p14.1-15.3 deletion and the pathogenesis of NELL1. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Sitosterolemia is a rare, autosomal recessively inherited disorder of lipid metabolism caused by mutations in the "ATP-binding cassette, subfamily G" member 5 and 8 proteins (encoded by the ABCG5 and ABCG8 genes, respectively), which play critical roles in the intestinal and biliary excretion of plant sterols. We report the clinical features and treatment outcomes of an 18-month-old Japanese girl with sitosterolemia, who presented with multiple linear and intertriginous xanthomas around the joint areas. Serum lipid analyses revealed elevated levels of total cholesterol (T-Chol: 866 mg/dL), low density lipoprotein-cholesterol (LDL-C: 679 mg/dL), and plant sterols (sitosterol: 24.6 mg/dL, campesterol: 19.2 mg/dL, stigmasterol: 1.8 mg/dL). Compound heterozygous mutations (p.R419H and p.R389H) were identified in ABCG5 . The patient was placed on a low cholesterol/low plant sterol diet and treated with colestimide (a bile acid sequestrant) and ezetimibe (an NPC1L1 inhibitor). Serum T-Chol and LDL-C levels decreased to normal within 2 mo, and plant sterol levels decreased by 30% within 4 mo. The xanthomas regressed gradually, and almost completely disappeared after 1.5 yr of treatment. No further reductions of plant sterol levels were observed. Long-term follow-up is important to verify appropriate therapeutic goals to prevent premature atherosclerosis and coronary artery disease.

Aggrecan, encoded by ACAN , is a major proteoglycan component of the extracellular matrix in the growth plate and articular cartilage. Aggrecan provides the hydrated gel structure important for the load-bearing properties of joints and plays a key role in cartilage and bone morphogenesis. At least 25 pathological ACAN mutations have been identified in patients with highly variable phenotypes of syndromic or non-syndromic short stature. This review provides an overview of the current understanding of ACAN and the clinical and genetic findings concerning aggrecan-associated diseases.

Sitosterolemia is a very rare autosomal recessive lipoprotein metabolic disorder caused by homozygous or compound heterozygous mutations in one of the two adenosine triphosphate-binding cassette transporter genes, ABCG5 and ABCG8. Sitosterolemia is clinically characterized by xanthomas and atherosclerosis, arthritis, fever, hemolysis and macrothrombocytopenia even in early childhood. We described a 16-month-old girl, who had numerous yellowish-brown intertriginous xanthomas along the skin creases on the extremities with severe hypercholesterolemia and elevated plant sterol levels. Histopathologically, xanthoma showed aggregation of foam cells in the dermis with a zone of mucin deposits in the dermal papilla. Electron microscopy showed numerous membrane-bound lipid droplets and multivesicular lipid bodies in the foam cells, a round cell containing lipid droplets in the basal cell layer and abundant mucin deposits just beneath the basal lamina. Diagnosis of sitosterolemia was confirmed by DNA sequencing showing compound heterozygosity for previously reported missense mutations in exon 9 of ABCG5. Infants presenting with multiple xanthomas should be investigated for sitosterolemia, if there is no family history of dyslipidemia., (© 2016 Japanese Dermatological Association.)

The etiology of idiopathic short stature (ISS) and Leri-Weill dyschondrosteosis (LWD) in European patients is known to include SHOX mutations and copy-number variations (CNVs) involving SHOX and/or the highly evolutionarily conserved non-coding DNA elements (CNEs) flanking the gene. However, the frequency and types of SHOX abnormalities in non-European patients and the clinical importance of mutations in the CNEs remains to be clarified. Here, we performed systematic molecular analyses of SHOX for 328 Japanese patients with ISS or LWD. SHOX abnormalities accounted for 3.8% of ISS and 50% of LWD cases. CNVs around SHOX were identified in 16 cases, although the ~47 kb deletion frequently reported in European patients was absent in our cases. Probably damaging mutations and benign/silent substitutions were detected in four cases, respectively. Although CNE-linked substitutions were detected in 15 cases, most of them affected poorly conserved nucleotides and were shared by unaffected individuals. These results suggest that the frequency and mutation spectrum of SHOX abnormalities are comparable between Asian and European patients, with the exception of a European-specific downstream deletion. Furthermore, this study highlights the clinical importance and genetic heterogeneity of the SHOX-flanking CNVs, and indicates a limited clinical significance of point mutations in the CNEs.

Phenylketonuria (PKU) and related hyperphenylalaninemia (HPA) are caused by a deficiency in hepatic phenylalanine hydroxylase (PAH). The incidence of PKU in Nagasaki prefecture is higher than that in all parts of Japan (1/15 894 vs 1/120 000). To investigate the genetic background of patients with HPA in Nagasaki prefecture, mutation analysis was done in 14 patients with PKU or mild HPA. Homozygous or compound heterozygous PAH mutations were identified in all the patients. The spectrum of PAH mutations in the cohort was broad and similar to those in all parts of Japan and East Asian countries. R53H is the most common mutation in patients with mild HPA. The present results provide further support for genotype-phenotype correlations in patients with HPA. The high incidence of PKU in Nagasaki, the westernmost part of Japan, might be due to migration of people with PAH mutations from China and Korea, and geographic factors., (© 2016 Japan Pediatric Society.)

Multiple mutations in SOX2 have been identified in patients with ocular anomalies and/or pituitary dysfunction. Here, we identified SOX2 abnormalities in nine patients. The molecular defects included one missense, one nonsense and four frameshift mutations, and three submicroscopic deletions involving SOX2. Three of the six mutations and all deletions were hitherto unreported. The breakpoints determined in one deletion were located within Alu repeats and accompanied by an overlap of 11 bp. Three of the six mutations encoded SOX2 proteins that lacked in vitro transactivation activity for the HESX1 promoter, whereas the remaining three generated proteins with ∼15-∼20% of transactivation activity. All cases manifested ocular anomalies of various severities, together with several complications including arachnoid cyst and hamartoma. There was no apparent correlation between the residual activity and clinical severity. The results indicate that molecular defects in SOX2 are highly variable and include Alu repeat-mediated genomic rearrangements. Our data provide further evidence for wide phenotypic variation of SOX2 abnormalities and the lack of genotype-phenotype correlation in patients carrying SOX2 lesions.

Background: The human SLC25A13 gene encodes citrin, the liver-type mitochondrial aspartate/glutamate carrier isoform 2 (AGC2), and SLC25A13 mutations cause citrin deficiency (CD), a disease entity that encompasses different age-dependant clinical phenotypes such as Adult-onset Citrullinemia Type II (CTLN2) and Neonatal Intrahepatic Cholestasis caused by Citrin Deficiency (NICCD). The analyses of SLC25A13 gene and its protein/mRNA products remain reliable tools for the definitive diagnoses of CD patients, and so far, the SLC25A13 mutation spectrum in Chinese CD patients has not been well-characterized yet., Methods and Results: By means of direct DNA sequencing, cDNA cloning and SNP analyses, 16 novel pathogenic mutations, including 9 missense, 4 nonsense, 1 splice-site, 1 deletion and 1 large transposal insertion IVS4ins6kb (GenBank accession number KF425758), were identified in CTLN2 or NICCD patients from China, Japan and Malaysia, respectively, making the SLC25A13 variations worldwide reach the total number of 81. A large NICCD cohort of 116 Chinese cases was also established, and the 4 high-frequency mutations contributed a much larger proportion of the mutated alleles in the patients from south China than in those from the north (χ(2) = 14.93, P<0.01), with the latitude of 30°N as the geographic dividing line in mainland China., Conclusions: This paper further enriched the SLC25A13 variation spectrum worldwide, and formed a substantial contribution to the in-depth understanding of the genotypic feature of Chinese CD patients.

Combined pituitary hormone deficiency (CPHD), isolated hypogonadotropic hypogonadism (IHH), Kallmann syndrome (KS), and septo-optic dysplasia (SOD) are genetically related conditions caused by abnormal development of the anterior midline in the forebrain. Although mutations in the fibroblast growth factor receptor 1 (FGFR1) gene have been implicated in the development of IHH, KS, and SOD, the relevance of FGFR1 abnormalities to CPHD remains to be elucidated. Here, we report a Japanese female patient with CPHD and FGFR1 haploinsufficiency. The patient was identified through copy-number analyses and direct sequencing of FGFR1 performed for 69 patients with CPHD. The patient presented with a combined deficiency of GH, LH and FSH, and multiple neurological abnormalities. In addition, normal TSH values along with a low free T4 level indicated the presence of central hypothyroidism. Molecular analyses identified a heterozygous ~ 8.5 Mb deletion involving 56 genes and pseudogenes. None of these genes except FGFR1 have been associated with brain development. No FGFR1 abnormalities were identified in the remaining 68 patients, although two patients carried nucleotide substitutions (p.V102I and p.S107L) that were assessed as benign polymorphism by in vitro functional assays. These results indicate a possible role of FGFR1 in anterior pituitary function and the rarity of FGFR1 abnormalities in patients with CPHD.

We report a de novo heterozygous 5,013,940 bp terminal deletion of chromosome 15q26 in a 13 9/12 -year-old Japanese girl with short stature (-3.9 SD), mild mental retardation, and ventricular septal defect (VSD). This terminal deletion involved IGF1R but not NR2F2, and was associated with an addition of telomere repeat sequences (TTAGGG) at the end of the truncated chromosome. The results provide further support for the notion that terminal deletions are healed by de novo addition of telomere sequences essential for chromosome stability and DNA replication. Furthermore, while growth failure and mental retardation are primarily explained by loss of IGF1R, the occurrence of VSD might suggest the existence of a cardiac anomaly gene, other than the candidate cardiac anomaly gene NR2F2, in the deleted region.

Context: Mutations of multiple transcription factor genes involved in pituitary development have been identified in a minor portion of patients with combined pituitary hormone deficiency (CPHD). However, copy number aberrations involving such genes have been poorly investigated in patients with CPHD., Objective: We aimed to report the results of mutation and gene copy number analyses in patients with CPHD., Subjects and Methods: Seventy-one Japanese patients with CPHD were examined for mutations and gene copy number aberrations affecting POU1F1, PROP1, HESX1, LHX3, LHX4, and SOX3 by PCR-direct sequencing and multiplex ligation-dependent probe amplification. When a deletion was indicated, it was further studied by fluorescence in situ hybridization, oligoarray comparative genomic hybridization, and serial sequencing for long PCR products encompassing the deletion junction., Results: We identified a de novo heterozygous 522,009-bp deletion involving LHX4 in a patient with CPHD (GH, TSH, PRL, LH, and FSH deficiencies), anterior pituitary hypoplasia, ectopic posterior pituitary, and underdeveloped sella turcica. We also identified five novel heterozygous missense substitutions (p.V201I and p.H387P in LHX4, p.T63M and p.A322T in LHX3, and p.V53L in SOX3) that were assessed as rare variants by sequencing analyses for control subjects and available parents and by functional studies and in silico analyses., Conclusions: The results imply the rarity of abnormalities affecting the six genes in patients with CPHD and the significance of the gene copy number analysis in such patients.

Heterozygous mutations of the gene encoding transcription factor OTX2 were recently shown to be responsible for ocular as well as pituitary abnormalities. Here, we describe a patient with unilateral anophthalmia and short stature. Endocrine evaluation of the hypothalamic-pituitary axis revealed isolated growth hormone deficiency (IGHD) with small anterior pituitary gland, invisible stalk, ectopic posterior lobe, and right anophthalmia on brain magnetic resonance imaging. DNA was analyzed for mutations in the HESX1, SOX2, and OTX2 genes. Molecular analysis yielded a novel heterozygous OTX2 mutation (c.270A>T, p.R90S) within the homeodomain. Functional analysis revealed that the mutation inhibited both the DNA binding and transactivation activities of the protein. This novel loss-of-function mutation is associated with anophthalmia and IGHD in a patient of Sephardic Jewish descent. We recommend that patients with GH deficiency and ocular malformation in whom genetic analysis for classic transcription factor genes (PROP1, POU1F1, HESX1, and LHX4) failed to identify alterations should be checked for the presence of mutations in the OTX2 gene.

Context: Although recent studies have suggested a positive role of OTX2 in pituitary as well as ocular development and function, detailed pituitary phenotypes in OTX2 mutations and OTX2 target genes for pituitary function other than HESX1 and POU1F1 remain to be determined., Objective: We aimed to examine such unresolved issues., Subjects: We studied 94 Japanese patients with various ocular or pituitary abnormalities., Results: We identified heterozygous p.K74fsX103 in case 1, p.A72fsX86 in case 2, p.G188X in two unrelated cases (3 and 4), and a 2,860,561-bp microdeletion involving OTX2 in case 5. Clinical studies revealed isolated GH deficiency in cases 1 and 5; combined pituitary hormone deficiency in case 3; abnormal pituitary structures in cases 1, 3, and 5; and apparently normal pituitary function in cases 2 and 4, together with ocular anomalies in cases 1-5. The wild-type Orthodenticle homeobox 2 (OTX2) protein transactivated the GNRH1 promoter as well as the HESX1, POU1F1, and IRBP (interstitial retinoid-binding protein) promoters, whereas the p.K74fsX103-OTX2 and p.A72fsX86-OTX2 proteins had no transactivation functions and the p.G188X-OTX2 protein had reduced ( approximately 50%) transactivation functions for the four promoters, with no dominant-negative effect. cDNA screening identified positive OTX2 expression in the hypothalamus., Conclusions: The results imply that OTX2 mutations are associated with variable pituitary phenotype, with no genotype-phenotype correlations, and that OTX2 can transactivate GNRH1 as well as HESX1 and POU1F1.

Background/aims: TAC3 and TACR3 have recently been shown to be causative genes for an autosomal recessive form of isolated hypogonadotropic hypogonadism (IHH). Here, we report a Japanese female with IHH and compound heterozygous TACR3 mutations and her heterozygous parents, and discuss the primary lesion for IHH and clinical findings., Case Report: This female was identified through mutation analysis of TAC3 and TACR3 in 57 patients with IHH. At 24 years of age, an initial standard GnRH test showed poor gonadotropin response (LH <0.2-0.6 IU/l), whereas the second GnRH test performed after GnRH priming (100 microg i.m. for 5 consecutive days) revealed ameliorated gonadotropin responses (LH 0.3-6.4 IU/l; FSH 2.2-9.6 IU/l). The mother exhibited several features suggestive of mild IHH, whereas the father showed an apparently normal phenotype., Results: She had a paternally derived nonsense mutation at exon 1 (Y145X) and a maternally inherited single nucleotide (G) deletion from the conserved 'GT' splice donor site of intron 1 (IVS1+1delG)., Conclusions: The results suggest hypothalamic dysfunction as the primary cause for IHH in patients with biallelic TACR3 mutations and clinical manifestation in heterozygous females, together with the rarity of TAC3 and TACR3 mutations in patients with IHH., (Copyright 2010 S. Karger AG, Basel.)

Unlabelled: CONTEX: Although GH values measured by an immunoassay usually reflect GH bioactivities, discrepancy exists between immunoactivity and bioactivity in a rare condition known as 'bioinactive GH'., Objective: To report an immunologically anomalous but considerably bioactive GH., Methods: We performed mutational and functional analyses of GH1 in a 7-year-old Japanese boy with short stature (-3.0 s.d.) in whom serum GH values measured with a Tosoh immunoassay kit were all undetectable in three provocation tests, whereas urine GH value measured with a Hitachi immunoassay kit was within the normal range. Serum IGF-1 was at a low-normal range, and IGF-binding protein-3 was below the normal range., Results: Mutation analysis showed a missense GH produced by a novel GH1 mutation (p.D116E) of paternal origin and a frameshift mutation (p.Q68fsX106) of maternal origin. Genotype-phenotype correlations in this family and in vitro functional studies indicated that the p.D116E-GH was immeasurable with the Tosoh kit but was measurable, though maybe not precise, with a Daiichi kit, and had a reduced in vivo bioactivity. The p.Q68fsX106 yielded no GH protein., Conclusions: The results suggest that the p.D116E affects the GH epitope primarily recognized by the Tosoh kit but not by the Hitachi or the Daiichi kits, thereby producing an immunologically anomalous but considerably bioactive GH. The presence of such a hormone discordant for immunoactivity and bioactivity should be kept in mind, to allow for an appropriate assessment of endocrine data.

Context: OTX2 is a transcription factor gene essential for eye development. Although recent studies suggest the involvement of OTX2 in pituitary function, there is no report demonstrating a positive role of OTX2 in the pituitary function., Objective: The objective of the study was to report the results of functional studies indicating the relevance of OTX2 to pituitary function., Patient: A Japanese female patient with bilateral anophthalmia was found to have short stature (height, -3.3 sd) and isolated partial GH deficiency (peak serum GH 3.1 and 9.7 mug/liter after insulin and arginine stimulations, respectively; serum IGF-I 37 ng/ml) at 3 yr 9 months of age. Magnetic resonance imaging delineated apparently normal pituitary gland., Results: Mutation analysis showed a de novo heterozygous frameshift mutation (c.402insC) that is predicted to retain the homeodomain but lose the transactivation domain. Functional studies revealed that the wild-type and mutant OTX2 proteins localized to the nucleus and bound to the target sequences within the IRBP (interstitial retinoid-binding protein), HESX1 (HESX homeobox 1), and POU1F1 promoters. Furthermore, the wild-type OTX2 protein markedly transactivated the promoters of IRBP ( approximately 27-fold), HESX1 ( approximately 4.5-fold), and POU1F1 ( approximately 19-fold), whereas the mutant OTX2 protein barely retained the transactivation activities and had no dominant-negative effects., Conclusions: The results provide direct evidence for OTX2 being involved in the pituitary function. It is likely that the heterozygous severe OTX2 loss-of-function mutation caused GH deficiency and short stature, primarily because of decreased transactivation function for HESX1 and POU1F1.

Although short-stature homeobox-containing gene (SHOX ) haploinsufficiency is responsible for Léri-Weill dyschondrosteosis (LWD), the molecular defect has not been identified in approximately 20% of Japanese LWD patients. Furthermore, although high prevalence of microdeletions affecting SHOX is primarily ascribed to the presence of repeat sequences such as Alu elements around SHOX, it remains to be determined whether microdeletions are actually mediated by repeat sequences. We performed multiple ligation probe amplification (MLPA) assay in six Japanese LWD patients with apparently normal SHOX, followed by fluorescent in situ hybridization (FISH) analysis and sequencing for polymerase chain reaction (PCR) products encompassing the deletion junctions in patients with abnormal MLPA patterns. Consequently, heterozygous intragenic deletions were identified in three cases, i.e., a 5,906-bp deletion involving exons 4-5 in case 1, a 5,594-bp deletion involving exons 4-6a in case 2, and a 50,199-bp deletion involving exons 4-6b in case 3. The deletion breakpoints of cases 1 and 2 were present in nonrepeat sequences, whereas those of case 3 resided within Alu elements. The results suggest that cryptic SHOX intragenic deletions account for a small fraction of LWD and that microdeletions affecting SHOX can be generated by repeat-sequence-mediated aberrant recombinations and by nonhomologous end joining.

We report on a sclerosing bone dysplasia, associated with cutis laxa, enamel dysplasia, and mental retardation. The patient was a 17-year-old Japanese boy of normal height and muscular build. Cutis laxa with prominent veins in the scalp and abdominal wall and delayed eruption of permanent teeth attracted the attention of clinicians in infancy and adolescence, respectively. The clinical manifestations included a progeroid facial appearance with prognathism, wrinkled skin, and interdigital webbing. The intelligence quotient was estimated at 60. Enamel dysplasia was histologically confirmed. Skeletal changes included calvarial hyperostosis, sclerosis of the skull base, an enlarged, sclerotic mandible, broad clavicles and ribs, and diaphyseal undermodeling of the tubular bones. Metaepiphyseal sclerosis or longitudinal striation was found in the long bones. Metaphyseal equivalents of the axial skeleton showed dense osteosclerosis. These clinical and radiological manifestations overlapped with those of Lenz-Majewski syndrome. Unlike the classical phenotype of the disorder, however, he did not show brachymesophalangy with proximal symphalangism or growth failure. The present case may be considered to fall in the mildest end in the phenotypic continuum of Lenz-Majewski syndrome, suggesting that the clinical spectrum of the disorder may be broader than currently thought.