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Recently, de novo heterozygous variants in DDX3X have been reported in about 1.5% of 2659 females with previously unexplained intellectual disability (ID). We report on the identification of DDX3X variants in two unrelated girls with clinical features of Toriello-Carey Syndrome (T-CS). In patient 1, the recurrent variant c.1703C>T; p.(P568L) was identified when reconsidering X-linked de novo heterozygous variants in exome sequencing data. In patient 2, the DDX3X variant c.1600C>G; p.(R534G) was also detected by exome sequencing. Based on these data, de novo heterozygous DDX3X variants should be considered not only in females with unexplained ID, but also in individuals with a clinical diagnosis of T-CS., (© 2017 Wiley Periodicals, Inc.)

Background: Adams-Oliver syndrome (AOS) is a rare disorder characterized by congenital limb defects and scalp cutis aplasia. In a proportion of cases, notable cardiac involvement is also apparent. Despite recent advances in the understanding of the genetic basis of AOS, for the majority of affected subjects, the underlying molecular defect remains unresolved. This study aimed to identify novel genetic determinants of AOS., Methods and Results: Whole-exome sequencing was performed for 12 probands, each with a clinical diagnosis of AOS. Analyses led to the identification of novel heterozygous truncating NOTCH1 mutations (c.1649dupA and c.6049_6050delTC) in 2 kindreds in which AOS was segregating as an autosomal dominant trait. Screening a cohort of 52 unrelated AOS subjects, we detected 8 additional unique NOTCH1 mutations, including 3 de novo amino acid substitutions, all within the ligand-binding domain. Congenital heart anomalies were noted in 47% (8/17) of NOTCH1-positive probands and affected family members. In leukocyte-derived RNA from subjects harboring NOTCH1 extracellular domain mutations, we observed significant reduction of NOTCH1 expression, suggesting instability and degradation of mutant mRNA transcripts by the cellular machinery. Transient transfection of mutagenized NOTCH1 missense constructs also revealed significant reduction in gene expression. Mutant NOTCH1 expression was associated with downregulation of the Notch target genes HEY1 and HES1, indicating that NOTCH1-related AOS arises through dysregulation of the Notch signaling pathway., Conclusions: These findings highlight a key role for NOTCH1 across a range of developmental anomalies that include cardiac defects and implicate NOTCH1 haploinsufficiency as a likely molecular mechanism for this group of disorders., (© 2015 American Heart Association, Inc.)

We report on a patient carrying a de novo interstitial deletion of chromosomal region 6q23.2-24.1. Interstitial deletions of 6q are rarely reported in the literature. Indeed, only four patients with interstitial deletions overlapping partially with the deleted region in our patient are described in the literature. The aberration was detected by GTG-banding. The size of the deletion was further refined by array-CGH and subsequently fine mapped by quantitative real-time PCR. The exact size of the deletion and the sequence composition of the breakpoints were determined by breakpoint spanning PCR and subsequent sequencing. The patient presented with microcephaly, short stature, patent ductus arteriosus, sensorineural hearing loss, mental retardation, reduced speech development, and abnormal behaviour. The deletion disrupts the gene EYA4. Mutations within this gene are associated with postlingual sensorineural hearing loss. The sequencing of the breakpoint indicated non homologous end joining as the most likely mechanism leading to the rearrangement.

The Shprintzen-Goldberg syndrome (SGS) is a disorder of unknown cause comprising craniosynostosis, a marfanoid habitus and skeletal, neurological, cardiovascular, and connective-tissue anomalies. There are no pathognomonic signs of SGS and diagnosis depends on recognition of a characteristic combination of anomalies. Here, we describe 14 persons with SGS and compare their clinical findings with those of 23 previously reported individuals, including two families with more than one affected individual. Our analysis suggests that there is a characteristic facial appearance, with more than two thirds of all individuals having hypertelorism, down-slanting palpebral fissures, a high-arched palate, micrognathia, and apparently low-set and posteriorly rotated ears. Other commonly reported manifestations include hypotonia in at least the neonatal period, developmental delay, and inguinal or umbilical hernia. The degree of reported intellectual impairment ranges from mild to severe. The most common skeletal manifestations in SGS were arachnodactyly, pectus deformity, camptodactyly, scoliosis, and joint hypermobility. None of the skeletal signs alone is specific for SGS. Our study includes 14 mainly German individuals with SGS evaluated over a period of 10 years. Given that only 23 other persons with SGS have been reported to date worldwide, we suggest that SGS may be more common than previously assumed.