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The X-linked NONO gene encodes Non-Pou Domain-Containing Octamer-Binding Protein, a multifunctional member of the DBHS family involved in transcriptional regulation, RNA splicing and DNA repair. Pathogenic variants in NONO cause Intellectual Developmental Disorder, X-linked Syndromic (MIM #300967), characterised by intellectual disability, neurodevelopmental delay, cardiomyopathy, such as left ventricular non-compaction (LVNC), and congenital heart defects such as including atrial septal defect (ASD), ventricular septal defect (VSD), patent ductus arteriosus (PDA), and patent foramen ovale (PFO). This study reports three new patients with pathogenic hemizygous frameshift variants in NONO identified with exome sequencing, broadening the clinical presentation. The patients present with neurodevelopmental delay, macrocephaly, agenesis or hypoplasia of the corpus callosum and LVNC, confirming previous findings. These findings contribute to the understanding of the phenotypic diversity in patients with NONO pathogenic variants and highlight the need for further investigation of genotype-phenotype correlations, particularly with regard to early cardiac development, and prenatal presentations., Competing Interests: Conflict of interest statement The authors declare that they have no conflict of interest., (Copyright © 2024. Published by Elsevier Masson SAS.)

TRIT1 encodes a tRNA isopentenyl transferase that allows a strong interaction between the mini helix and the codon. Recent reports support the TRIT1 bi-allelic alterations as the cause of an autosomal recessive disorder, named combined oxydative phophorylation deficiency 35, with microcephaly, developmental disability, and epilepsy. The phenotype is due to decreased mitochondrial function, with deficit of i6A37 in cytosolic and mitochondrial tRNA. Only 10 patients have been reported. We report on two new patients with four novel variants, and confirm the published clinical TRIT1 deficient phenotype stressing the possibility of both very severe, with generalized pharmaco-resistant seizures, and mild phenotypes., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2022 Elsevier Masson SAS. All rights reserved.)

We report the screening of a large panel of genes in a series of 100 fetuses (98 families) affected with severe renal defects. Causative variants were identified in 22% of cases, greatly improving genetic counseling. The percentage of variants explaining the phenotype was different according to the type of phenotype. The highest diagnostic yield was found in cases affected with the ciliopathy-like phenotype (11/15 families and, in addition, a single heterozygous or a homozygous Class 3 variant in PKHD1 in three unrelated cases with autosomal recessive polycystic kidney disease). The lowest diagnostic yield was observed in cases with congenital anomalies of the kidney and urinary tract (9/78 families and, in addition, Class 3 variants in GREB1L in three unrelated cases with bilateral renal agenesis). Inheritance was autosomal recessive in nine genes (PKHD1, NPHP3, CEP290, TMEM67, DNAJB11, FRAS1, ACE, AGT, and AGTR1), and autosomal dominant in six genes (PKD1, PKD2, PAX2, EYA1, BICC1, and MYOCD). Finally, we developed an original approach of next-generation sequencing targeted RNA sequencing using the custom capture panel used for the sequencing of DNA, to validate one MYOCD heterozygous splicing variant identified in two male siblings with megabladder and inherited from their healthy mother., (© 2022 Wiley Periodicals LLC.)

Background: The clinical significance of 16p13.11 duplications remains controversial while frequently detected in patients with developmental delay (DD), intellectual deficiency (ID) or autism spectrum disorder (ASD). Previously reported patients were not or poorly characterised. The absence of consensual recommendations leads to interpretation discrepancy and makes genetic counselling challenging. This study aims to decipher the genotype-phenotype correlations to improve genetic counselling and patients' medical care., Methods: We retrospectively analysed data from 16 013 patients referred to 12 genetic centers for DD, ID or ASD, and who had a chromosomal microarray analysis. The referring geneticists of patients for whom a 16p13.11 duplication was detected were asked to complete a questionnaire for detailed clinical and genetic data for the patients and their parents., Results: Clinical features are mainly speech delay and learning disabilities followed by ASD. A significant risk of cardiovascular disease was noted. About 90% of the patients inherited the duplication from a parent. At least one out of four parents carrying the duplication displayed a similar phenotype to the propositus. Genotype-phenotype correlations show no impact of the size of the duplicated segment on the severity of the phenotype. However, NDE1 and miR-484 seem to have an essential role in the neurocognitive phenotype., Conclusion: Our study shows that 16p13.11 microduplications are likely pathogenic when detected in the context of DD/ID/ASD and supports an essential role of NDE1 and miR-484 in the neurocognitive phenotype. Moreover, it suggests the need for cardiac evaluation and follow-up and a large study to evaluate the aortic disease risk., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Study Question: Can cytochrome P450 oxidoreductase deficiency (PORD) be revealed in adult women with menstrual disorders and/or infertility?, Summary Answer: PORD was biologically and genetically confirmed in five adult women with chronically elevated serum progesterone (P) who were referred for oligo-/amenorrhea and/or infertility., What Is Known Already: PORD is an autosomal recessive disease typically diagnosed in neonates and children with ambiguous genitalia and/or skeletal abnormalities. It is responsible for the decreased activity of several P450 enzymes, including CYP21A2, CYP17A1 and CYP19A1, that are involved in adrenal and/or gonadal steroidogenesis. Little is known about the optimal way to investigate and treat patients with adult-onset PORD., Study Design, Size, Duration: In this series, we report five adult females who were evaluated in three tertiary endocrine reproductive departments between March 2015 and September 2018., Participants/materials, Setting, Methods: Five women aged 19-38 years were referred for unexplained oligo-/amenorrhea and/or infertility. Genetic testing excluded 21-hydroxylase deficiency (21OH-D), initially suspected due to the increased 17-hydroxyprogesterone (17-OHP) levels. Extensive phenotyping, steroid profiling by mass spectrometry, pelvic imaging and next-generation sequencing of 84 genes involved in gonadal and adrenal disorders were performed in all patients. IVF followed by frozen embryo transfer (ET) under glucocorticoid suppression therapy was performed for two patients., Main Results and the Role of Chance: All patients had oligomenorrhea or amenorrhea. None had hyperandrogenism. Low-normal serum estradiol (E2) and testosterone levels contrasted with chronically increased serum P and 17-OHP levels, which further increased after adrenocorticotrophic hormone (ACTH) administration. Despite excessive P, 17OH-P and 21-deoxycortisol rise after ACTH stimulation suggesting non-classic 21OH-D, CYP21A2 sequencing did not support this hypothesis. Basal serum cortisol levels were low to normal, with inadequate response to ACTH in some women, suggesting partial adrenal insufficiency. All patients harbored rare biallelic POR mutations classified as pathogenic or likely pathogenic according to the American College of Medical Genetics and Genomics standards. Pelvic imaging revealed bilateral ovarian macrocysts in all women. IVF was performed for two women after retrieval of a normal oocyte number despite very low E2 levels during ovarian stimulation. Frozen ET under glucocorticoid suppression therapy led to successful pregnancies., Limitations, Reasons for Caution: The number of patients described here is limited and these data need to be confirmed on a larger number of women with non-classic PORD., Wider Implications of the Findings: The diagnosis of PORD must be considered in infertile women with chronically elevated P and 17OH-P levels and ovarian macrocysts. Differentiation of this entity from non-classic 21OH-D is important, as the multiple enzyme deficiency requires a specific management. Successful fertility induction is possible by IVF, providing that P levels be sufficiently suppressed by glucocorticoid therapy prior to implantation., Study Funding/competing Interest(s): No specific funding was used for this study. There are no potential conflicts of interest., Trial Registration Number: N/A., (© The Author(s) 2020. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The heterogeneous nuclear ribonucleoprotein (HNRNP) genes code for a set of RNA-binding proteins that function primarily in the spliceosome C complex. Pathogenic variants in these genes can drive neurodegeneration, through a mechanism involving excessive stress-granule formation, or developmental defects, through mechanisms that are not known. Here, we report four unrelated individuals who have truncating or missense variants in the same C-terminal region of hnRNPR and who have multisystem developmental defects including abnormalities of the brain and skeleton, dysmorphic facies, brachydactyly, seizures, and hypoplastic external genitalia. We further identified in the literature a fifth individual with a truncating variant. RNA sequencing of primary fibroblasts reveals that these HNRNPR variants drive significant changes in the expression of several homeobox genes, as well as other transcription factors, such as LHX9, TBX1, and multiple HOX genes, that are considered fundamental regulators of embryonic and gonad development. Higher levels of retained intronic HOX sequences and lost splicing events in the HOX cluster are observed in cells carrying HNRNPR variants, suggesting that impaired splicing is at least partially driving HOX deregulation. At basal levels, stress-granule formation appears normal in primary and transfected cells expressing HNRNPR variants. However, these cells reveal profound recovery defects, where stress granules fail to disassemble properly, after exposure to oxidative stress. This study establishes an essential role for HNRNPR in human development and points to a mechanism that may unify other "spliceosomopathies" linked to variants that drive multi-system congenital defects and are found in hnRNPs., (Copyright © 2019 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

CHES (cerebellar hypoplasia with endosteal sclerosis) syndrome (OMIM#213002) associates hypomyelination, cerebellar atrophy, hypogonadism and hypodontia. So far, only five patients have been described. The condition is of neonatal onset. Patients have severe psychomotor delay and moderate to severe intellectual disability. Inheritance is assumed to be autosomal recessive due to recurrence in sibs, consanguinity of parents and absence of vertical transmission. CHES syndrome is reminiscent of 4H-leukodystrophy, a recessive-inherited affection due to variations in genes encoding subunits of the RNA polymerase III (POLR3A-POLR3B-POLR1C). POLR3B variants have been identified in one CHES patient. Here we report on a novel CHES patient, carrying compound heterozygous variations in POLR3B. This report confirms affiliation of CHES to POLR3-related disorders and suggests that CHES syndrome represents a severe form of 4H-leukodystrophy.

Background: Cohesinopathies are rare neurodevelopmental disorders arising from a dysfunction in the cohesin pathway, which enables chromosome segregation and regulates gene transcription. So far, eight genes from this pathway have been reported in human disease. STAG1 belongs to the STAG subunit of the core cohesin complex, along with five other subunits. This work aimed to identify the phenotype ascribed to STAG1 mutations., Methods: Among patients referred for intellectual disability (ID) in genetics departments worldwide, array-comparative genomic hybridisation (CGH), gene panel, whole-exome sequencing or whole-genome sequencing were performed following the local diagnostic standards., Results: A mutation in STAG1 was identified in 17 individuals from 16 families, 9 males and 8 females aged 2-33 years. Four individuals harboured a small microdeletion encompassing STAG1 ; three individuals from two families had an intragenic STAG1 deletion. Six deletions were identified by array-CGH, one by whole-exome sequencing. Whole-exome sequencing found de novo heterozygous missense or frameshift STAG1 variants in eight patients, a panel of genes involved in ID identified a missense and a frameshift variant in two individuals. The 17 patients shared common facial features, with wide mouth and deep-set eyes. Four individuals had mild microcephaly, seven had epilepsy., Conclusions: We report an international series of 17 individuals from 16 families presenting with syndromic unspecific ID that could be attributed to a STAG1 deletion or point mutation. This first series reporting the phenotype ascribed to mutation in STAG1 highlights the importance of data sharing in the field of rare disorders., Competing Interests: Competing interests: MTC and AB are employees of GeneDx., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Mandibulofacial dysostosis, Guion-Almeida type (MFDGA) is a recently delineated multiple congenital anomalies/mental retardation syndrome characterized by the association of mandibulofacial dysostosis (MFD) with external ear malformations, hearing loss, cleft palate, choanal atresia, microcephaly, intellectual disability, oesophageal atresia (OA), congenital heart defects (CHDs), and radial ray defects. MFDGA emerges as a clinically recognizable entity, long underdiagnosed due to highly variable presentations. The main differential diagnoses are CHARGE and Feingold syndromes, oculoauriculovertebral spectrum, and other MFDs. EFTUD2, located on 17q21.31, encodes a component of the major spliceosome and is disease causing in MFDGA, due to heterozygous loss-of-function (LoF) mutations. Here, we describe a series of 36 cases of MFDGA, including 24 previously unreported cases, and we review the literature in order to delineate the clinical spectrum ascribed to EFTUD2 LoF. MFD, external ear anomalies, and intellectual deficiency occur at a higher frequency than microcephaly. We characterize the evolution of the facial gestalt at different ages and describe novel renal and cerebral malformations. The most frequent extracranial malformation in this series is OA, followed by CHDs and skeletal abnormalities. MFDGA is probably more frequent than other syndromic MFDs such as Nager or Miller syndromes. Although the wide spectrum of malformations complicates diagnosis, characteristic facial features provide a useful handle., (© 2014 WILEY PERIODICALS, INC.)

Background: Oesophageal atresia (OA) and mandibulofacial dysostosis (MFD) are two congenital malformations for which the molecular bases of syndromic forms are being identified at a rapid rate. In particular, the EFTUD2 gene encoding a protein of the spliceosome complex has been found mutated in patients with MFD and microcephaly (MIM610536). Until now, no syndrome featuring both MFD and OA has been clearly delineated., Results: We report on 10 cases presenting with MFD, eight of whom had OA, either due to de novo 17q21.31 deletions encompassing EFTUD2 and neighbouring genes or de novo heterozygous EFTUD2 loss-of-function mutations. No EFTUD2 deletions or mutations were found in a series of patients with isolated OA or isolated oculoauriculovertebral spectrum (OAVS)., Conclusions: These data exclude a contiguous gene syndrome for the association of MFD and OA, broaden the spectrum of clinical features ascribed to EFTUD2 haploinsufficiency, define a novel syndromic OA entity, and emphasise the necessity of mRNA maturation through the spliceosome complex for global growth and within specific regions of the embryo during development. Importantly, the majority of patients reported here with EFTUD2 lesions were previously diagnosed with Feingold or CHARGE syndromes or presented with OAVS plus OA, highlighting the variability of expression and the wide range of differential diagnoses.

The association of pelvi-ureteric junction obstruction (PUJO) and rapidly fatal persistent pulmonary hypertension of the newborn (PPHN) has been observed in two male siblings. PUJO was also observed in a maternal uncle, whose daughter suffered from vesico-ureteral reflux (VUR). In both patients, histopathologic study of the lungs showed misalignment of pulmonary veins (MAPV), which is a rare autosomal recessive condition leading to severe PPHN and death within the neonatal period. It has occasionally been described associated with PUJO. The authors point out that: i: MAPV has to be carefully searched in case of PPHN; ii: PUJO could be an important finding associated with MAPV, and the only prenatal indication of this lethal condition.

We describe a 24-weeks-old fetus with Fryns' syndrome (FS) and two erupted incisors. The present observations is another example of prenatal diagnosis of FS, based on ultrasonographically detected hernia diaphragmatica and cystic hygroma. It also adds an hitherto non described finding in FS. The presence of prenatally erupted teeth without any similar family history is discussed.