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We report clinical and molecular findings in three Japanese patients with N-acetylneuraminic acid synthetase-congenital disorder of glycosylation (NANS-CDG). Patient 1 exhibited a unique constellation of clinical features including marked hydrocephalus, spondyloepimetaphyseal dysplasia (SEMD), and thrombocytopenia which is comparable to that of an infant reported by Faye-Peterson et al., whereas patients 2 and 3 showed Camera-Genevieve type SMED with intellectual/developmental disability which is currently known as the sole disease name for NANS-CDG. Molecular studies revealed a maternally inherited likely pathogenic c.207del:p.(Arg69Serfs*57) variant and a paternally derived likely pathogenic c.979_981dup:p.(Ile327dup) variant in patient 1, a homozygous likely pathogenic c.979_981dup:p.(Ile327dup) variant caused by maternal segmental isodisomy involving NANS in patient 2, and a paternally inherited pathogenic c.133−12T>A variant leading to aberrant splicing and a maternally inherited likely pathogenic c.607T>C:p.(Tyr203His) variant in patient 3 (reference mRNA: NM_018946.4). The results, together with previously reported data, imply that (1) NANS plays an important role in postnatal growth and fetal brain development; (2) SMED is recognizable at birth and shows remarkable postnatal evolution; (3) NANS-CDG is associated with low-normal serum sialic acid, obviously elevated urine N-acetylmannosamine, and normal N- and O-glycosylation of serum proteins; and (4) NANS-CDG is divided into Camera-Genevieve type and more severe Faye-Peterson type. [ABSTRACT FROM AUTHOR]

Isolated hypogonadotropic hypogonadism (IHH), combined pituitary hormone deficiency (CPHD), and septo-optic dysplasia (SOD) constitute a disease spectrum whose etiology remains largely unknown. This study aimed to clarify whether mutations in SMCHD1, an epigenetic regulator gene, might underlie this disease spectrum. SMCHD1 is a causative gene for Bosma arhinia microphthalmia syndrome characterized by arhinia, microphthalmia and IHH. We performed mutation screening of SMCHD1 in patients with etiology-unknown IHH (n = 31) or CPHD (n = 43, 19 of whom also satisfied the SOD diagnostic criteria). Rare variants were subjected to in silico analyses and classified according to the American College of Medical Genetics and Genomics guidelines. Consequently, a rare likely pathogenic variant, p.Asp398Asn, was identified in one patient. The patient with p.Asp398Asn exhibited CPHD, optic nerve hypoplasia, and a thin retinal nerve fiber layer, and therefore satisfied the criteria of SOD. This patient showed a relatively low DNA methylation level of the 52 SMCHD1-target CpG sites at the D4Z4 locus. Exome sequencing for the patient excluded additional variants in other IHH/CPHD-causative genes. In vitro assays suggested functional impairment of the p.Asp398Asn variant. These results provide the first indication that SMCHD1 mutations represent a rare genetic cause of the HH-related disease spectrum. [ABSTRACT FROM AUTHOR]

Background: X chromosome inactivation (XCI) is an indispensable process in the development of human female embryos. Reportedly, XCI occurs when a blastocyst contains 10–12 embryonic progenitor cells. To date, it remains unclear whether XCI ratios are normally preserved in Klinefelter syndrome (KS) patients with 47,XXY karyotype. Methods: We examined XCI ratios in 18 KS patients through DNA methylation analysis for the polymorphic trinucleotide locus in the AR gene. The results of the KS patients were compared to previous data from healthy young women. Results: XCI ratios in KS patients followed a normal distribution. Skewed XCI was observed in two patients, one of whom exhibited extremely skewed XCI. The frequencies of skewed and extremely skewed XCI in the KS cohort were comparable to those in healthy women. Conclusion: This study confirmed the rarity of skewed XCI in KS patients. These results indicate that the presence of a supernumerary X chromosome during the cleavage and early blastocyst stages does not affect the developmental tempo of embryos. Our data deserve further validation. [ABSTRACT FROM AUTHOR]

Although NDNF was recently reported as a novel causative gene for congenital hypogonadotropic hypogonadism (CHH), this conclusion has yet to be validated. In this study, we sequenced NDNF in 61 Japanese CHH patients. No variants, except for nine synonymous substitutions that appear to have no effect on splice-site recognition, were identified in NDNF coding exons or flanking intronic sequences. These results indicate the rarity of NDNF variants in CHH patients and highlight the genetic heterogeneity of CHH. [ABSTRACT FROM AUTHOR]

Purpose: Bardet-Biedl syndrome (BBS) is a rare autosomal recessive disorder characterized by retinal dystrophy, renal dysfunction, central obesity, mental impairment, polydactyly, and hypogonadism. Only limited information on BBS is available from Japanese patients. In addition, there are currently no reports of Japanese patients with BBS caused by BBS10 mutations. The purpose of this study was to present the characteristics of a Japanese patient with BBS caused by BBS10 mutations.Patient and methods: The patient was a 22-year-old Japanese woman. Comprehensive ophthalmic examinations, including visual acuity measurements, perimetry, electroretinography (ERG), fundus autofluorescence imaging, and optical coherence tomography, were performed. Trio-based whole-exome sequencing was performed to identify potential pathogenic mutations, confirmed by Sanger sequencing.Results: The patient showed neither renal malformation nor dysfunction, and visual impairment seemed to be relatively mild for BBS. The fundus examination revealed diffuse retinal degeneration without pigmentary deposits, and ERG scans showed undetectable responses. She had a history of surgically corrected polydactyly, and displayed symptoms of obesity. There was also a menstrual irregularity that could require progestin administration. Genetic analysis revealed compound heterozygous BBS10 mutations in the patient: a novel missense mutation c.98G>A [p.(G33E)], and a novel nonsense mutation c.2125A>T [p.(R709*)].Conclusion: To our knowledge, this is the first description of a Japanese patient with BBS caused by BBS10 mutations. The clinical characteristics of our patient were mild, as neither renal impairment nor legal blindness was observed. Early diagnosis would play a role in providing counseling, and in some cases, therapeutic interventions for BBS patients. [ABSTRACT FROM AUTHOR]

Several epidemiological studies have suggested that the incidence of male reproductive organ malformations, including hypospadias or cryptorchidism, has increased due to fetal-stage exposure to environmental pollutants. However, the association of chemical exposure with the expression of target regulatory genes in the tissues of patients has not yet been reported. Because experimental approaches or clinical trials in human studies are limited, especially those using fetal and/or infants, it is difficult to obtain clear physiological evidence of mechanisms underlying male reproductive malformations. Thus, the lack of physiological evidence makes this issue controversial. We analyzed preputial tissues from patients with hypospadias (n = 23) and phimosis (n = 16). The atypical CYP1 family genes, CYP1A1 and CYP1B1, are potential biomarkers of environmental chemical exposure. We then compared the expression levels of CYP1A1 and CYP1B1 between hypospadias and phimosis samples by quantitative RT-PCR analysis. The mRNA expression levels of SRD5A2 and AR also were measured, because the androgen-related genes involved in the onset of disorders of male reproductive system. A significantly higher CYP1B1 expression level and a lower AR expression level were observed in the hypospadias groups than in the phimosis group. Positive correlations (P < 0.001) between the mRNA expression levels of the CYP1 family and SRD5A2 were found in patients with hypospadias but not in those with phimosis. Moreover, the methylation levels of the four genes were determined by bisulfite genomic sequencing. Although the SRD5A2 promoter region showed moderate methylation, no methylation was detected in CYP1A1, CYP1B1, or AR. There was no significant difference in SRD5A2 promoter methylation level between hypospadias and phimosis patients. Negative correlations were found between the methylation level of SRD5A2, especially at the − 221 Sp1 site, and the CYP1 family mRNA expression levels (CYP1A1, p = 0.002; CYP1B1, p = 0.007) in hypospadias patients, but not in phimosis patients. The significant positive association of mRNA expression level and the negative association of methylation level of the SRD5A2 gene with the mRNA expression levels of CYP1 family genes in the preputial tissue seem to indicate the chemical exposure of patients with hypospadias. [ABSTRACT FROM AUTHOR]

SETD1B (SET domain containing 1B) is a component of SET1 histone methyltransferase complex, which mediates the methylation of histone H3 on lysine 4 (H3K4). Here, we describe two unrelated individuals with de novo variants in SETD1B identified by trio-based whole exome sequencing: c.5524C>T, p.(Arg1842Trp) and c.5575C>T, p.(Arg1859Cy). The two missense variants occurred at evolutionarily conserved amino acids and are located within the SET domain, which plays a pivotal role in catalyzing histone methylation. Previous studies have suggested that de novo microdeletions in the 12q24.3 region encompassing SETD1B were associated with developmental delays, intellectual disabilities, autism/autistic behavior, large stature and craniofacial anomalies. Comparative mapping of 12q24.3 deletions refined the candidate locus, indicating KDM2B and SETD1B to be the most plausible candidate genes for the pathogenicity of 12q24.3 deletion syndrome. Our cases showed epilepsy, developmental delay, intellectual disabilities, autistic behavior and craniofacial dysmorphic features, which are consistent with those of individuals with de novo 12q24.31 deletions. Therefore, our study suggests that SETD1B aberration is likely to be the core defect in 12q24.3 deletion syndrome. [ABSTRACT FROM AUTHOR]

RASopathies are autosomal dominant disorders caused by mutations in more than 10 known genes that regulate the RAS/MAPK pathway. Noonan syndrome (NS) is a RASopathy characterized by a distinctive facial appearance, musculoskeletal abnormalities, and congenital heart defects. We have recently identified mutations in RIT1 in patients with NS. To delineate the clinical manifestations in RIT1 mutation-positive patients, we further performed a RIT1 analysis in RASopathy patients and identified 7 RIT1 mutations, including two novel mutations, p.A77S and p.A77T, in 14 of 186 patients. Perinatal abnormalities, including nuchal translucency, fetal hydrops, pleural effusion, or chylothorax and congenital heart defects, are observed in all RIT1 mutation-positive patients. Luciferase assays in NIH 3T3 cells demonstrated that the newly identified RIT1 mutants, including p.A77S and p.A77T, and the previously identified p.F82V, p.T83P, p.Y89H, and p.M90I, enhanced Elk1 transactivation. Genotype-phenotype correlation analyses of previously reported NS patients harboring RIT1, PTPN11, SOS1, RAF1, and KRAS revealed that hypertrophic cardiomyopathy (56 %) was more frequent in patients harboring a RIT1 mutation than in patients harboring PTPN11 (9 %) and SOS1 mutations (10 %). The rates of hypertrophic cardiomyopathy were similar between patients harboring RIT1 mutations and patients harboring RAF1 mutations (75 %). Short stature (52 %) was less prevalent in patients harboring RIT1 mutations than in patients harboring PTPN11 (71 %) and RAF1 (83 %) mutations. These results delineate the clinical manifestations of RIT1 mutation-positive NS patients: high frequencies of hypertrophic cardiomyopathy, atrial septal defects, and pulmonary stenosis; and lower frequencies of ptosis and short stature. [ABSTRACT FROM AUTHOR]

Paternal uniparental disomy 14 (UPD(14)pat) and epimutations and microdeletions affecting the maternally derived 14q32.2 imprinted region lead to a unique constellation of clinical features such as facial abnormalities, small bell-shaped thorax with a coat-hanger appearance of the ribs, abdominal wall defects, placentomegaly, and polyhydramnios. In this study, we performed comprehensive clinical studies in patients with UPD(14)pat (n=23), epimutations (n=5), and microdeletions (n=6), and revealed several notable findings. First, a unique facial appearance with full cheeks and a protruding philtrum and distinctive chest roentgenograms with increased coat-hanger angles to the ribs constituted the pathognomonic features from infancy through childhood. Second, birth size was well preserved, with a median birth length of ±0 SD (range, −1.7 to +3.0 SD) and a median birth weight of +2.3 SD (range, +0.1 to +8.8 SD). Third, developmental delay and/or intellectual disability was invariably present, with a median developmental/intellectual quotient of 55 (range, 29-70). Fourth, hepatoblastoma was identified in three infantile patients (8.8%), and histological examination in two patients showed a poorly differentiated embryonal hepatoblastoma with focal macrotrabecular lesions and well-differentiated hepatoblastoma, respectively. These findings suggest the necessity of an adequate support for developmental delay and periodical screening for hepatoblastoma in the affected patients, and some phenotypic overlap between UPD(14)pat and related conditions and Beckwith-Wiedemann syndrome. On the basis of our previous and present studies that have made a significant contribution to the clarification of underlying (epi)genetic factors and the definition of clinical findings, we propose the name 'Kagami-Ogata syndrome' for UPD(14)pat and related conditions. [ABSTRACT FROM AUTHOR]

Pseudoautosomal region 1 (PAR1) contains SHOX, in addition to seven highly conserved non-coding DNA elements (CNEs) with cis-regulatory activity. Microdeletions involving SHOX exons 1-6a and/or the CNEs result in idiopathic short stature (ISS) and Leri-Weill dyschondrosteosis (LWD). Here, we report six rare copy-number variations (CNVs) in PAR1 identified through copy-number analyzes of 245 ISS/LWD patients and 15 unaffected individuals. The six CNVs consisted of three microduplications encompassing SHOX and some of the CNEs, two microduplications in the SHOX 3′-region affecting one or four of the downstream CNEs, and a microdeletion involving SHOX exon 6b and its neighboring CNE. The amplified DNA fragments of two SHOX-containing duplications were detected at chromosomal regions adjacent to the original positions. The breakpoints of a SHOX-containing duplication resided within Alu repeats. A microduplication encompassing four downstream CNEs was identified in an unaffected father-daughter pair, whereas the other five CNVs were detected in ISS patients. These results suggest that microduplications involving SHOX cause ISS by disrupting the cis-regulatory machinery of this gene and that at least some of microduplications in PAR1 arise from Alu-mediated non-allelic homologous recombination. The pathogenicity of other rare PAR1-linked CNVs, such as CNE-containing microduplications and exon 6b-flanking microdeletions, merits further investigation. [ABSTRACT FROM AUTHOR]

Maternal uniparental disomy 14 (UPD(14)mat) and related (epi)genetic aberrations affecting the 14q32.2 imprinted region result in a clinically recognizable condition which is recently referred to as Temple Syndrome (TS). Phenotypic features in TS include pre- and post-natal growth failure, prominent forehead, and feeding difficulties that are also found in Silver-Russell Syndrome (SRS). Thus, we examined the relevance of UPD(14)mat and related (epi)genetic aberrations to the development of SRS in 85 Japanese patients who satisfied the SRS diagnostic criteria proposed by Netchine et al and had neither epimutation of the H19-DMR nor maternal uniparental disomy 7. Pyrosequencing identified hypomethylation of the DLK1-MEG3 intergenic differentially methylated region (IG-DMR) and the MEG3-DMR in two cases. In both cases, microsatellite analysis showed biparental transmission of the homologs of chromosome 14, with no evidence for somatic mosaicism with full or segmental maternal isodisomy involving the imprinted region. FISH and array comparative genomic hybridization revealed neither deletion of the two DMRs nor discernible copy number alteration in the 14q32.2 imprinted region. Methylation patterns were apparently normal in other six disease-associated DMRs. In addition, a thorough literature review revealed a considerable degree of phenotypic overlap between SRS and TS, although body asymmetry was apparently characteristic of SRS. The results indicate the occurrence of epimutation affecting the IG-DMR and the MEG3-DMR in the two cases, and imply that UPD(14)mat and related (epi)genetic aberrations constitute a rare but important underlying factor for SRS. [ABSTRACT FROM AUTHOR]

Whole-exome sequencing (WES) is becoming a standard tool for detecting nucleotide changes, and determining whether WES data can be used for the detection of copy-number variations (CNVs) is of interest. To date, several algorithms have been developed for such analyses, although verification is needed to establish if they fit well for the appropriate purpose, depending on the characteristics of each algorithm. Here, we performed WES CNV analysis using the eXome Hidden Markov Model (XHMM). We validated its performance using 27 rare CNVs previously identified by microarray as positive controls, finding that the detection rate was 59%, or higher (89%) with three or more targets. XHMM can be effectively used, especially for the detection of >200 kb CNVs. XHMM may be useful for deletion breakpoint detection. Next, we applied XHMM to genetically unsolved patients, demonstrating successful identification of pathogenic CNVs: 1.5-1.9-Mb deletions involving NSD1 in patients with unknown overgrowth syndrome leading to the diagnosis of Sotos syndrome, and 6.4-Mb duplication involving MECP2 in affected brothers with late-onset spasm and progressive cerebral/cerebellar atrophy confirming the clinical suspect of MECP2 duplication syndrome. The possibility of an 'exome-first' approach for clinical genetic investigation may be considered to save the cost of multiple investigations. [ABSTRACT FROM AUTHOR]

Although copy-number variations (CNVs) in Y-chromosomal azoospermia factor (AZF) regions have been associated with the risk of spermatogenic failure (SF), the precise frequency, genomic basis and clinical consequences of these CNVs remain unclear. Here we performed multiplex ligation-dependent probe amplification (MLPA) analysis of 56 Japanese SF patients and 65 control individuals. We compared the results of MLPA with those of conventional sequence-tagged site PCR analyses. Eleven simple and complex CNVs, including three hitherto unreported variations, were identified by MLPA. Seven of the 11 CNVs were undetectable by conventional analyses. CNVs were widely distributed in AZF regions and shared by ~60% of the patients and ~40% of the controls. Most breakpoints resided within locus-specific repeats. The majority of CNVs, including the most common gr/gr deletion, were identified in the patient and control groups at similar frequencies, whereas simple duplications were observed exclusively in the patient group. The results imply that AZF-linked CNVs are more frequent and heterogeneous than previously reported. Non-allelic homologous recombination likely underlies these CNVs. Our data confirm the functional neutrality of the gr/gr deletion in the Japanese population. We also found a possible association between AZF-linked simple duplications and SF, which needs to be evaluated in future studies. [ABSTRACT FROM AUTHOR]

We report duplications of maternally derived chromosome 11p15 involving CDKN1C encoding a negative regulator for cell proliferation in three Japanese patients (cases 1 and 2 from family A and case 3 from family B) with Silver-Russell syndrome (SRS) phenotype lacking hemihypotrophy. Chromosome analysis showed 46,XX,der(16)t(11;16)(p15.3;q24.3)mat in case 1, 46,XY,der(16)t(11;16)(p15.3;q24.3)mat in case 2 and a de novo 46,XX,der(17)t(11;17)(p15.4;q25.3) in case 3. Genomewide oligonucleotide-based array comparative genomic hybridization, microsatellite analysis, pyrosequencing-based methylation analysis and direct sequence analysis revealed the presence of maternally derived extra copies of the distal chromosome 11p involving the wild-type CDKN1C (a ~7.98 Mb region in cases 1 and 2 and a ~4.43 Mb region in case 3). The results, in conjunction with the previous findings in patients with similar duplications encompassing CDKN1C and in those with intragenic mutations of CDKN1C, imply that duplications of CDKN1C, as well as relatively mild gain-of-function mutations of CDKN1C lead to SRS subtype that usually lack hemihypotrophy. [ABSTRACT FROM AUTHOR]

We report four patients with SRY-positive 46,XX testicular disorders of sex development (46,XX-TDSD) (cases 1-4). Case 1 exhibited underdeveloped external genitalia with hypospadias, case 2 manifested micropenis and cases 3 and 4 showed normal external genitalia. The Xp;Yp translocations occurred between the X- and the Y-differential regions in case 1, between PRKX and inverted PRKY in case 2 and between the X-chromosomal short arm pseudoautosomal region and the Y-differential regions in cases 3 and 4. The distance of the Yp breakpoint from SRY was ∼0.75 Mb in case 1, ∼6.5 Mb in case 2, ∼2.3 Mb in case 3 and ∼72 kb in case 4. The Xp;Yp translocation occurred within an 87-bp homologous segment of PRKX and PRKY in case 2, and between non-homologous regions with addition of an 18-bp sequence of unknown origin in case 4. X-inactivation analysis revealed random inactivation in cases 1-4. The results argue against the notion that undermasculinization in 46,XX-TDSD is prone to occur when translocated Yp materials are small (<100 kb of the Y-differential region), and imply that the Xp;Yp translocations result from several mechanisms including non-allelic homologous recombination and non-homologous end joining. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Increased intratumoral expression of aromatase, the key enzyme for estrogen biosynthesis, is predicted to be of critical importance in the development of breast cancer. Recently, several germline rearrangements at 15q21 have been shown to cause overexpression of the aromatase gene CYP19A1 and resulting aromatase excess syndrome. To determine whether submicroscopic genomic rearrangements at 15q21 are involved in aromatase overexpression in breast cancer tissues, we investigated copy-number alterations in genomic DNA obtained from 44 tumor samples. Comparative genomic hybridization analysis identified no deletion or duplication at 15q21 in the 44 samples. These results, in conjunction with previous data, indicate that aromatase overexpression in breast cancer tissues is likely to result from a promoter switch of CYP19A1 and/or accumulation of CYP19A1-expressing cells, rather than from cryptic transactivation of CYP19A1 because of genomic rearrangements at 15q21. [ABSTRACT FROM AUTHOR]

Paternal uniparental disomy 14 (UPD(14)pat) results in a unique constellation of clinical features, and a similar phenotypic constellation is also caused by microdeletions involving the DLK1-MEG3 intergenic differentially methylated region (IG-DMR) and/or the MEG3-DMR and by epimutations (hypermethylations) affecting the DMRs. However, relative frequency of such underlying genetic causes remains to be clarified, as well as that of underlying mechanisms of UPD(14)pat, that is, trisomy rescue (TR), gamete complementation (GC), monosomy rescue (MR), and post-fertilization mitotic error (PE). To examine this matter, we sequentially performed methylation analysis, microsatellite analysis, fluorescence in situ hybridization, and array-based comparative genomic hybridization in 26 patients with UPD(14)pat-like phenotype. Consequently, we identified UPD(14)pat in 17 patients (65.4%), microdeletions of different patterns in 5 patients (19.2%), and epimutations in 4 patients (15.4%). Furthermore, UPD(14)pat was found to be generated through TR or GC in 5 patients (29.4%), MR or PE in 11 patients (64.7%), and PE in 1 patient (5.9%). Advanced maternal age at childbirth (≥35 years) was predominantly observed in the MR/PE subtype. The results imply that the relative frequency of underlying genetic causes for the development of UPD(14)pat-like phenotype is different from that of other imprinting disorders, and that advanced maternal age at childbirth as a predisposing factor for the generation of nullisomic oocytes through non-disjunction at meiosis 1 may be involved in the development of MR-mediated UPD(14)pat. [ABSTRACT FROM AUTHOR]

The prevalence of spermatogenic failure (SF) has gradually increased during the past few decades at least in several countries. Although multiple factors would be involved in this phenomenon, one important factor would be excessive estrogen effects via estrogen receptors (ERs). Thus, we performed haplotype analysis of ESR2 encoding ERβ in 125 Japanese SF patients and 119 age-matched control males, using single nucleotide polymorphisms (SNPs) 1-9 that are widely distributed on the ∼120-kb genomic sequence of ESR2. Consequently, a linkage disequilibrium (LD) block was detected in an ∼60-kb region encompassing SNPs 2-7 in both groups, and four major estimated haplotypes were identified within the LD block. Furthermore, the most prevalent 'TGTAGA' haplotype was found to be significantly associated with SF, with the P-value obtained by the Cochran-Armitage trend test (0.0029) being lower than that obtained by a 100 000-times permutation test (0.0038) to cope with the problem of multiple comparisons. The results, in conjunction with our previous data indicating lack of a susceptibility factor on ESR1 encoding ERα, imply that the specific 'TGTAGA' haplotype of ESR2 raises the susceptibility to the development of SF. [ABSTRACT FROM AUTHOR]

We hypothesized that single-nucleotide polymorphisms (SNPs) of genes involved in environmental endocrine disruptors (EEDs) metabolism might influence the risk of male genital malformations. In this study, we explored for association between 384 SNPs in 15 genes (AHR, AHRR, ARNT, ARNT2, NR1I2, RXRA, RXRB, RXRG, CYP1A1, CYP1A2, CYP1B1, CYP2B6, CYP3A4, CYP17A1 and CYP19A1) and risk of cryptorchidism (CO) and hypospadias (HS) in 334 Japanese (JPN) males (141 controls, 95 CO and 98 HS) and 187 Italian (ITA) males (129 controls and 58 CO). In the JPN study group, five SNPs from ARNT2 (rs2278705 and rs5000770), CYP1A2 (rs2069521), CYP17A1 (rs4919686) and NR1I2 (rs2472680) were significantly associated at both allelic and genotypic levels with risk of at least one genital malformation phenotype. In the ITA study group, two SNPs in AHR (rs3757824) and ARNT2 (rs1020397) were significantly associated with risk of CO. Interaction analysis of the positive SNPs using multifactor dimensionality reduction demonstrated that synergistic interaction between rs2472680, rs4919686 and rs5000770 had 62.81% prediction accuracy for CO (P=0.011) and that between rs2069521 and rs2278705 had 69.98% prediction accuracy for HS (P=0.001) in JPN population. In a combined analysis of JPN and ITA population, the most significant multi-locus association was observed between rs5000770 and rs3757824, which had 65.70% prediction accuracy for CO (P=0.055). Our findings indicate that genetic polymorphisms in genes involved in EED metabolism are associated with risk of CO and HS. [ABSTRACT FROM AUTHOR]

Background: The 'coat-hanger' sign of the ribs with a bell-shaped thorax has been known as a radiological hallmark of the paternal uniparental disomy 14 (upd(14)pat). Objective: To quantitatively determine the differences in thoracic deformity between upd(14)pat and other bone diseases with thoracic hypoplasia and to establish the age-dependent evolution. Materials and methods: The subjects comprised 11 children with upd(14)pat. The angle between the 6th posterior rib and the horizontal axis was measured (coat hanger angle; CHA). The ratio of the mid- to widest thorax diameter (M/W ratio) was calculated for the bell-shaped thorax. Results: CHA ranged from +28.5 to 45° (mean; 35.1° ± 5.2) in upd(14)pat, and from −19.8 to 21° (−3.3 ± 13°) in bone dysplasias ( p < 0.01). The M/W ratio ranged from 58% to 93% (75.4 ± 10) in upd(14)pat, and from 80% to 92% (86.8 ± 3.3) in bone dysplasias ( p < 0.05). Serial radiographs revealed that CHA remained constant during early childhood, while the M/W ratio gradually increased with age. Conclusion: The 'coat-hanger' sign of upd(14)pat provides a distinctive radiological gestalt that makes it possible to differentiate the disorder from other skeletal dysplasias. By contrast, the bell-shaped thorax is significant only in the neonatal period. [ABSTRACT FROM AUTHOR]

Prader-Willi syndrome (PWS) is primarily caused by deletions involving the paternally derived imprinted region at chromosome 15q11.2-q13 and maternal uniparental disomy 15 (upd(15)mat). The underlying mechanisms for upd(15)mat include trisomy rescue (TR), gamete complementation (GC), monosomy rescue and post-fertilization mitotic error, and TR/GC is mediated by non-disjunction at maternal meiosis 1 (M1) or meiosis 2 (M2). Of these factors involved in the development of upd(15)mat, M1 non-disjunction is a maternal age-dependent phenomenon. We studied 117 Japanese patients with PWS and identified deletions in 84 patients (Deletion group) and TR/GC type upd(15)mat through M1 non-disjunction in 15 patients (TR/GC (M1) group), together with other types of abnormalities. Maternal age was significantly higher in TR/GC (M1) group than in Deletion group (median (range), 37 (35-45) versus 30 (19-42); P=1.0 × 10−7). Furthermore, delayed childbearing age became obvious since the year 2003 in Japan, and relative frequency of TR/GC (M1) group was significantly larger in patients born since the year 2003 than in those born until the year 2002. The results imply that the advanced maternal age at childbirth is a predisposing factor for the development of upd(15)mat because of increased M1 errors. [ABSTRACT FROM AUTHOR]

The course of renal involvement and hearing loss is much milder in most female X-linked Alport syndromes than in male patients. We examined the molecular mechanism of development of the disease in a female patient with severe Alport syndrome. The patient showed heavy proteinuria, hematuria, neurosensory hearing loss and primary amenorrhea. Renal biopsy findings of electron microscopy and immunostaining of the α5 chain of type IV collagen indicated a female X-linked Alport syndrome. G-banding chromosomal analysis showed a t(X;1)(q22.3;p36.32) balanced translocation. Analysis of the collagen type IV ( COL4A5) gene by genomic DNA sequencing, complementary DNA (cDNA) sequencing and multiplex ligation-dependent probe amplification assay showed no mutations or deletions/duplications of the gene. However, fluorescence in situ hybridization using the probes for exon 1 and exon 51 of the COL4A5 gene showed disruption of one copy of the gene. Replication R-banding chromosomal analysis indicated preferential inactivation of the normal X chromosome. This is the first report of severe Alport syndrome in a female patient carrying a balanced translocation between the chromosome X and 1 producing the disruption of one copy of COL4A5 gene and silencing of the other copy because of preferential inactivation of the normal X chromosome. Chromosomal abnormalities should be considered in female patients with severe forms of Alport syndrome. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Silver-Russell syndrome (SRS) is characterized by growth failure and dysmorphic features and is frequently caused by hypomethylation (epimutation) of the H19-DMR. Although molecular and clinical studies have extensively been performed for SRS patients themselves, such studies have not been carried out for placentas. We identified 20 epimutation-positive and 40 epimutation-negative Japanese SRS patients and obtained placental weight data from 12 epimutation-positive and ten epimutation-negative patients and paraffin-embedded placental tissues for molecular and histological examinations from three epimutation-positive and two epimutation-negative patients. Methylation patterns were comparable between leukocytes and placentas in both epimutation-positive and epimutation-negative patients. Epimutations resulted in virtually no IGF2 expression and biallelic slight H19 expression in the leukocytes and obviously reduced IGF2 expression of paternal origin and nearly normal H19 expression of maternal origin in the placentas. Epimutation-positive patients had characteristic body phenotype and small placentas with hypoplastic chorionic villi, and epimutation-negative patients had somewhat small placentas with hypoplastic chorionic villi or massive infarction. Furthermore, significant correlations were identified between the H19-DMR methylation index and the body and placental sizes and between the placental weight and the body size in the epimutation-positive patients, whereas such correlations were not detected for the head circumference. These results suggest (1) characteristic phenotype and reduced IGF2 expression in the epimutation-positive placentas; (2) similarities and differences in the epigenetic control of the IGF2–H19 domain between leukocytes and placentas; (3) a positive role of the IGF2 expression level, as reflected by the methylation index, in the determination of body and placental growth in epimutation-positive patients, except for the brain where IGF2 is expressed biallelically; (4) involvement of placental dysfunction in prenatal growth failure; and (5) relevance of both (epi)genetic factor(s) and environmental factor(s) to SRS in epimutation-negative patients. [ABSTRACT FROM AUTHOR]

Silver–Russell syndrome (SRS) is characterized by growth failure and dysmorphic features, and is frequently caused by hypomethylation of the paternally derived H19-DMR (epimutation). We observed 5 8/12-year-old female twins discordant for SRS. One twin exhibited SRS-compatible features, such as pre- and postnatal growth failure, relative macrocephaly, triangular face, left hemihypotrophy, and bilateral fifth finger clinodactyly, whereas the other twin showed apparently normal phenotype. Microsatellite analysis for 26 loci on multiple chromosomes showed monozygosity. Methylation analysis for the H19-DMR indicated epimutation in roughly half of cells in the affected twin and normal patterns in the unaffected twin and the parents. X-inactivation analysis revealed random X-inactivation with a nearly identical pattern between the twins. The discordant methylation pattern of the H19-DMR may primarily be due to a failure to maintain the DNA methyltransferase-1-dependent methylation imprint around the pre-implantation S phase, because such failure would result in the production of two different cell clones, one with normally methylated DMR and the other with demethylated DMR, leading to the separation of cells with different characters and resultant twinning. [ABSTRACT FROM AUTHOR]

Maternal uniparental disomy for chromosome 14 (upd(14)mat) causes clinically discernible features such as pre- and/or postnatal growth failure, hypotonia, obesity, small hands, and early onset of puberty. The monoallelic expression patterns at the 14q32.2 imprinted region are tightly related to methylation status of the DLK1–MEG3 intergenic differential methylation region (DMR) and the MEG3-DMR that are severely hypermethylated after paternal transmission and grossly hypomethylated after maternal transmission. We examined this imprinted region in a 2 2/12-year-old Japanese patient who was born with a normal birth size (length, +0.2 SD; weight, −0.5 SD) and showed postnatal growth failure (height, −3.1 SD; weight, −3.4 SD), hypotonia, frontal bossing, micrognathia, and small hands. Methylation analysis, genotyping analysis, and deletion analysis were performed with blood samples of the patient and the parents, showing that the DMRs of this patient were grossly hypomethylated in the absence of upd(14)mat and deletion of the DMRs. The results indicate the occurrence of an epimutation (hypomethylation) affecting the normally methylated DMRs of paternal origin, and imply that epimutations should be examined in patients with upd(14)mat-like phenotype.European Journal of Human Genetics (2008) 16, 1019–1023; doi:10.1038/ejhg.2008.90; published online 14 May 2008 [ABSTRACT FROM AUTHOR]

Although short-stature homeobox-containing gene ( SHOX ) haploinsufficiency is responsible for Léri–Weill dyschondrosteosis (LWD), the molecular defect has not been identified in ∼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. [ABSTRACT FROM AUTHOR]

Eutherian placenta, an organ that emerged in the course of mammalian evolution, provides essential architecture, the so-called feto-maternal interface, for fetal development by exchanging nutrition, gas and waste between fetal and maternal blood. Functional defects of the placenta cause several developmental disorders, such as intrauterine growth retardation in humans and mice. A series of new inventions and/or adaptations must have been necessary to form and maintain eutherian chorioallantoic placenta, which consists of capillary endothelial cells and a surrounding trophoblast cell layer(s). Although many placental genes have been identified, it remains unknown how the feto-maternal interface is formed and maintained during development, and how this novel design evolved. Here we demonstrate that retrotransposon-derived Rtl1 (retrotransposon-like 1), also known as Peg11 (paternally expressed 11), is essential for maintenance of the fetal capillaries, and that both its loss and its overproduction cause late-fetal and/or neonatal lethality in mice. [ABSTRACT FROM AUTHOR]

Urogenital birth defects are one of the common phenotypes observed in hereditary human disorders. In particular, limb malformations are often associated with urogenital developmental abnormalities, as the case for Hand–foot–genital syndrome displaying similar hypoplasia/agenesis of limbs and external genitalia. Split-hand/split-foot malformation (SHFM) is a syndromic limb disorder affecting the central rays of the autopod with median clefts of the hands and feet, missing central fingers and often fusion of the remaining ones. SHFM type 1 (SHFM1) is linked to genomic deletions or rearrangements, which includes the distal-less-related homeogenes DLX5 and DLX6 as well as DSS1. SHFM type 4 (SHFM4) is associated with mutations in p63, which encodes a p53-related transcription factor. To understand that SHFM is associated with urogenital birth defects, we performed gene expression analysis and gene knockout mouse model analyses. We show here that Dlx5, Dlx6, p63 and Bmp7, one of the p63 downstream candidate genes, are all expressed in the developing urethral plate (UP) and that targeted inactivation of these genes in the mouse results in UP defects leading to abnormal urethra formation. These results suggested that different set of transcription factors and growth factor genes play similar developmental functions during embryonic urethra formation. Human SHFM syndromes display multiple phenotypes with variations in addition to split hand foot limb phenotype. These results suggest that different genes associated with human SHFM could also be involved in the aetiogenesis of hypospadias pointing toward a common molecular origin of these congenital malformations.European Journal of Human Genetics (2008) 16, 36–44; doi:10.1038/sj.ejhg.5201925; published online 19 September 2007 [ABSTRACT FROM AUTHOR]

Purpose: The prevalence of low birth weight (LBW) is increased in subjects born after assisted reproduction technology (ART), and defective imprinting has frequently been identified in patients with Beckwith-Wiedermann and Angelman syndromes conceived by ART. Thus, we examined methylation pattern in a girl born after ART who had Silver-Russell syndrome (SRS) which can be caused by maternal uniparental disomy for chromosome 7 and by hypomethylation of the differentially methylated region (DMR) of H19. Methods: We examined methylation status of 31 cytosines at the CpG dinucleotides in the DMR of PEG1/MEST on 7q32.2 and 23 cytosines at the CpG dinucleotides in the DMR of H19 on 11p15, using leukocyte genomic DNA. Results: Eight of the 31 cytosines in the patient and four of the 31 cytosines in the father were hypermethylated in the PEG1/MEST-DMR. In the H19-DMR, no abnormal methylation pattern was identified in the patient. Conclusion: The results suggest that hypermethylation of paternally expressed genes including PEG1/MEST, which usually have growth-promoting effects, may be relevant to LBW in subjects conceived by ART. [ABSTRACT FROM AUTHOR]

Cartilage-hair hypoplasia (CHH), or metaphyseal dysplasia, McKusick type, is an autosomal recessive disease with diverse clinical manifestations. CHH is caused by mutations in RMRP (ribonuclease mitochondrial RNA processing), the gene encoding the RNA component of the ribonucleoprotein complex RNase MRP. A common founder mutation, 70A>G has been reported in the Finnish and Amish populations. We screened 11 Japanese patients with CHH for RMRP mutations and identified mutations in five probands, including three novel mutations (16-bp dup at +1, 168G>A, and 217C>T). All patients were compound heterozygotes for an insertion or duplication in the promoter or 5′-transcribed regions and a point mutation in the transcribed region. Two recurrent mutations were unique to the Japanese population: a 17-bp duplication at +3 and 218A>G. Haplotype analysis revealed that the two mutations common in Japanese individuals were contained within distinct haplotypes. Through this analysis, we have identified a unique mutation spectrum and founder mutations in the Japanese population. [ABSTRACT FROM AUTHOR]

Recently, a urate transporter, hURAT1 (human uric acid transporter 1) encoded by SLC22A12, was isolated from the human kidney. hURAT1 is presumed to play the central role in reabsorption of urate from glomerular filtrate. In the present study, we analyzed SLC22A12 in seven unrelated Japanese patients with renal hypouricemia whose serum level of urate was less than 1.0 mg/dl, and their family members. We performed direct DNA sequencing of the exon and exon-intron boundaries of SLC22A12 using genomic DNA. Six of the seven patients (86%) possess mutations in SLC22A12. In five patients, a homozygous G to A transition at nucleotide 774 within exon 4 of SLC22A12, which forms a stop codon (TGA) at codon 258 (TGG), was identified (W258X). In one patient, the C to T transition within exon 3, which changes threonine at codon 217 to methionine (T217 M), and the W258X mutation were found (compound heterozygote). Thus, among 12 mutational alleles in six patients, 11 were the W258X mutation (92%). Family members with the heterozygous W258X mutation (carriers) show relatively low levels of serum urate. The present study demonstrates that homozygous W258X mutation is the predominant genetic cause of idiopathic renal hypouricemia in Japanese patients. [ABSTRACT FROM AUTHOR]

Male embryonic mice with mutations in the X-linked aristaless-related homeobox gene (Arx) developed with small brains due to suppressed proliferation and regional deficiencies in the forebrain. These mice also showed aberrant migration and differentiation of interneurons containing γ-aminobutyric acid (GABAergic interneurons) in the ganglionic eminence and neocortex as well as abnormal testicular differentiation. These characteristics recapitulate some of the clinical features of X-linked lissencephaly with abnormal genitalia (XLAG) in humans. We found multiple loss-of-function mutations in ARX in individuals affected with XLAG and in some female relatives, and conclude that mutation of ARX causes XLAG. The present report is, to our knowledge, the first to use phenotypic analysis of a knockout mouse to identify a gene associated with an X-linked human brain malformation. [ABSTRACT FROM AUTHOR]

We report clinical and molecular findings in 15 Japanese mosaic females with r(X) chromosomes, 45,X/46,X,r(X), confirmed by fluorescence in situ hybridization (FISH) analysis for DXZ1 and whole X chromosome painting. Cases 1–3, 5–7, and 11–13 had mental retardation (MR), the remaining cases being free from MR. FISH analysis showed that XIST was absent from the r(X) chromosomes in cases 1–4 and was present on the r(X) chromosomes in cases 5–15. X-inactivation analysis for the methylation status of the AR gene indicated that, of eight cases with XIST-positive r(X) chromosomes in more than 10% (23%–62%) of lymphocytes (cases 5–12), cases 5–10 had selective X-inactivation, whereas cases 11 and 12 had active X disomy. Microsatellite analysis for multiple loci on the pericentromeric region revealed that, of 11 cases with r(X) chromosomes in more than 10% (13%–62%) of lymphocytes (cases 1, 2, and 4–12), cases 1, 2, and 5–10 had heterozygous alleles for at least one locus, whereas cases 4, 11, and 12 had single alleles for all the loci examined. The results suggest that the r(X) and normal X chromosomes could be of biparental or uniparental origin, and that mental status in females with r(X) chromosomes is determined by multiple factors, including the presence or absence of XIST on the r(X) chromosomes and the size and frequency of active r(X) chromosomes, in addition to co-incidental genetic and environmental factors. [ABSTRACT FROM AUTHOR]

We report a mother and two daughters with partial Xp monosomy. Clinical assessment for Turner phenotype revealed that the three females manifested low-normal to mild short stature (–1.6 to approximately –2.3 SD) and variable degrees of skeletal features, such as cubitus valgus, short 4th matacarpals, and Madelung deformity, but no soft tissue or visceral anomalies or gonadal dysfunction. Cytogenetic studies for lymphocytes showed that the karyotype was 45,X[3]/46,X,del(X)(p21.1)[27] in the mother and non-mosaic 46,X,del(X)(p21.1) in the two daughters. Fluorescence in situ hybridization and microsatellite analyses for 19 loci/regions on the X chromosome demonstrated that the del(Xp) chromosome was missing SHOX and had the breakpoint between DMD and CYBB. The results are consistent with the recently proposed notion that haploinsufficiency of SHOX results in not only short stature, but also Turner skeletal features in association with maturational effects of gonadal estrogens. The lack of soft tissue or visceral anomalies suggests the presence of the putative lymphogenic gene on the del(Xp) chromosome; the preservation of ovarian function appears to be compatible with meiotic pairing failure being relatively mild. [ABSTRACT FROM AUTHOR]

This paper describes a 12-year-old Japanese boy with coarctation of the aorta, renal hypoplasia, Turner/Noonan surface anomalies, and a 46,XY karyotype. Although the patient might represent an exceptional case of Noonan syndrome, the combination of the somatic stigmata appears to be consistent with a mutation of the putative lymphogenic gene(s) for Turner somatic stigmata. [ABSTRACT FROM AUTHOR]

Although clinical features in Turner syndrome have been well defined, underlying genetic factors have not been clarified. To deduce the factors leading to the development of clinical features, we took the following four steps: (1) assessment of clinical features in classic 45,X Turner syndrome; (2) review of clinical features in various female sex chromosome aberrations (karyotype-phenotype correlations); (3) assessment of factors that could lead to Turner features; and (4) correlation of the clinical features with the effects of specific factors. The results indicate that the clinical features in 45,X and in other female sex chromosome aberrations may primarily be determined by: (1) degree of global non-specific developmental defects caused by quantitative alteration of a euchromatic or noninactivated region; (2) dosage effect of a pseudoautosomal growth gene(s), a Y-specific growth gene(s), and an Xp-Yp homologous lymphogenic gene(s); and (3) degree of chromosome pairing failure in meiocytes that are destined to develop as oocytes in the absence of SRY. [ABSTRACT FROM AUTHOR]

Although the locus for X-linked recessive chondrodysplasia punctata (CDPX1) has been mapped to the region between PABX and DXS31 (the critical region is about 3 Mb long), the precise location within the critical region has not been determined. In this paper, we describe a boy with a 46,Y,der(X)t(X;Y)(p22.3;q11)mat karyotype and review the genotype-phenotype correlations in three male patients with the combination of apparent lack of clinical features of CDPX1 and a partial deletion of the critical region. The results suggest that the region defined by the two BssHII sites at 3180 and 3570 kb from the Xp telomere may be the target region for the CDPX1 locus. [ABSTRACT FROM AUTHOR]

Although sex chromosome aberrations are frequently associated with statural changes, the underlying factors have not been clarified. To define the factors leading to the statural changes, we took the following three steps: (1) determination of the mean adult height in non-mosaic Caucasian patients with sex chromosome aberrations reported in the literature (assessment of genetic height potential); (2) assessment of the validity of factors that could influence stature; and (3) correlation of the mean adult height with the effects of specific growth-related factors. The results indicate that the adult height in patients with sex chromosome aberrations may primarily be defined by the dosage effect of pseudoautosomal and Y-specific growth genes, together with the degree of growth disadvantage caused by alteration of the quantity of euchromatic or non-inactivated region. [ABSTRACT FROM AUTHOR]

This report describes androgenetic/biparental mosaicism in a 4-year-old Japanese girl with Beckwith-Wiedemann syndrome (BWS)-like and paternal uniparental disomy 14 (upd(14)pat)-like phenotypes. We performed methylation analysis for 18 differentially methylated regions on various chromosomes, genome-wide microsatellite analysis for a total of 90 loci and expression analysis of SNRPN in leukocytes. Consequently, she was found to have an androgenetic 46,XX cell lineage and a normal 46,XX cell lineage, with the frequency of the androgenetic cells being roughly calculated as 91% in leukocytes, 70% in tongue tissues and 79% in tonsil tissues. It is likely that, after a normal fertilization between an ovum and a sperm, the paternally derived pronucleus alone, but not the maternally derived pronucleus, underwent a mitotic division, resulting both in the generation of the androgenetic cell lineage by endoreplication of one blastomere containing a paternally derived pronucleus and in the formation of the normal cell lineage by union of paternally and maternally derived pronuclei. It appears that the extent of overall (epi)genetic aberrations exceeded the threshold level for the development of BWS-like and upd(14)pat-like phenotypes, but not for the occurrence of other imprinting disorders or recessive Mendelian disorders. [ABSTRACT FROM AUTHOR]

Although splicing errors due to single nucleotide variants represent a common cause of monogenic disorders, only a few variants have been shown to create new splice sites in exons. Here, we report an MAP3K1 splice variant identified in two siblings with 46,XY disorder of sex development. The patients carried a maternally derived c.2254C>T variant. The variant was initially recognized as a nonsense substitution leading to nonsense-mediated mRNA decay (p.Gln752Ter); however, RT-PCR for lymphoblastoid cell lines showed that this variant created a new splice donor site and caused 39 amino acid deletion (p.Gln752_Arg790del). All transcripts from the variant allele appeared to undergo altered splicing. The two patients exhibited undermasculinized genitalia with and without hypergonadotropism. Testosterone enanthate injections and dihydrotestosterone ointment applications yielded only slight increase in their penile length. Dihydrotestosterone-induced APOD transactivation was less significant in patients' genital skin fibroblasts compared with that in control samples. This study provides an example of nonsense-associated altered splicing, in which a highly potent exonic splice site was created. Furthermore, our data, in conjunction with the previous data indicating the association between MAP3K1 and androgen receptor signaling, imply that the combination of testicular dysgenesis and androgen insensitivity may be a unique phenotype of MAP3K1 abnormalities. [ABSTRACT FROM AUTHOR]

46,XY disorders of sex development (DSD) refer to a wide range of abnormal genitalia, including hypospadias, which affects ∼0.5% of male newborns. We identified three different nonsense mutations of CXorf6 in individuals with hypospadias and found that its mouse homolog was specifically expressed in fetal Sertoli and Leydig cells around the critical period for sex development. These data imply that CXorf6 is a causative gene for hypospadias. [ABSTRACT FROM AUTHOR]

This article describes the specific radiological findings of congenital lipoid adrenal hyperplasia (lipoid CAH) in a phenotypic female and karyotypic 46XY infant. Radiological examination showed enlarged bilateral adrenal glands with fatty accumulation and spared medulla. These findings are key to differentiating lipoid CAH from the diseases that cause adrenal insufficiency during early infancy, including other forms of congenital adrenal hyperplasia. [ABSTRACT FROM AUTHOR]

We report on a three-generation family (daughter, mother, and maternal grandmother) with a syndrome of inappropriate secretion of antidiuretic hormone (SIADH)-like condition in the absence of inappropriate ADH secretion. In the three females, a water load test showed severely reduced urinary water excretion, with the ratio of urine volume to the loaded water being 10-33% (normal value: 70.2±7.8%). Urinary AQP2 excretion was normal, as was the DNA sequence of AVPR2 and AQP2. The results suggest the presence of a new dominantly inherited disorder for tubular water resorption. [ABSTRACT FROM AUTHOR]