Project description:Conradi-Hünermann-Happle syndrome is a rare X-linked dominant syndrome affecting the skin, skeletal system, and eyes. Here, we report on a female patient with a de novo heterozygous missense mutation c.301C>T (p.Trp101Arg) of the EMP (emopamil binding protein) gene.
Project description:Conradi-Hünermann-Happle syndrome, or X-linked dominant chondrodysplasia punctata type 2 (CDPX2), is a genodermatosis caused by mutations in EBP. While typically lethal in males, females with CDPX2 generally manifest by infancy or childhood with variable features including congenital ichthyosiform erythroderma, chondrodysplasia punctata, asymmetric shortening of the long bones, and cataracts. We present a 36-year-old female with short stature, rhizomelic and asymmetric limb shortening, severe scoliosis, a sectorial cataract, and no family history of CDPX2. Whole exome sequencing (WES) revealed a p.Arg63del mutation in EBP, and biochemical studies confirmed a diagnosis of CDPX2. Short stature in combination with ichthyosis or alopecia, cataracts, and limb shortening in an adult should prompt consideration of a diagnosis of CDPX2. As in many genetic syndromes, the hallmark features of CDPX2 in pediatric patients are not readily identifiable in adults. This demonstrates the utility of WES as a diagnostic tool in the evaluation of adults with genetic disorders.
Project description:Conradi-Hünermann-Happle syndrome (CDPX2, OMIM 302960) is an inherited X-linked dominant variant of chondrodysplasia punctata which primarily affects the skin, bones, and eyes. CDPX2 patients display skin defects, including ichthyotic lesions, follicular atrophoderma, cicatricial alopecia, and less frequently ichthyosiform erythroderma, cataracts, and skeletal abnormalities consisting of short stature, asymmetric shortening of the limbs, epiphyseal stippling, and craniofacial defects. CDPX2 results from mutations in emopamil binding protein (EBP) gene. The aim of our study is to identify EBP mutation in a unique case of Conradi-Hünermann-Happle syndrome with rare psoriasiform lesions.
Project description:X-linked dominant chondrodysplasia punctata (CDPX2 or Conradi-Hünermann-Happle syndrome, MIM #302960) is caused by mutations in the EBP gene. Affected female patients present with Blaschkolinear ichthyosis, coarse hair or alopecia, short stature, and normal psychomotor development. The disease is usually lethal in boys. Nevertheless, few male patients have been reported; they carry a somatic mosaicism in EBP or present with Klinefelter syndrome. Here, we report CDPX2 patients belonging to a three-generation family, carrying the splice variant c.301 + 5 G > C in intron 2 of EBP. The grandfather carries the variant as mosaic state and presents with short stature and mild ichthyosis. The mother also presents with short stature and mild ichthyosis and the female fetus with severe limb and vertebrae abnormalities and no skin lesions, with random X inactivation in both. This further characterizes the phenotypical spectrum of CDPX2, as well as intrafamilial variability, and raises the question of differential EBP mRNA splicing between the different target tissues.
Project description:The Conradi-Hünermann Disease is a rare syndrome, which affects the cranial development and the anatomy of dental occlusion. After interdisciplinary treatment completion, the patient reached satisfactory facial anatomy, as well as regular occlusal relationship, attested 2 years of accompaniment.
Project description:Preterm birth (PTB) affects ~12% of pregnancies in the US. Despite its high mortality and morbidity, the molecular etiology underlying PTB has been unclear. Numerous studies have been devoted to identifying genetic factors in maternal and fetal genomes, but so far few genomic loci have been associated with PTB. By analyzing whole-genome sequencing data from 816 trio families, for the first time, we observed the role of fetal de novo mutations in PTB. We observed a significant increase in de novo mutation burden in PTB fetal genomes. Our genomic analyses further revealed that affected genes by PTB de novo mutations were dosage sensitive, intolerant to genomic deletions, and their mouse orthologs were likely developmentally essential. These genes were significantly involved in early fetal brain development, which was further supported by our analysis of copy number variants identified from an independent PTB cohort. Our study indicates a new mechanism in PTB occurrence independently contributed from fetal genomes, and thus opens a new avenue for future PTB research.
Project description:Novel protein-coding genes can arise either through re-organization of pre-existing genes or de novo. Processes involving re-organization of pre-existing genes, notably after gene duplication, have been extensively described. In contrast, de novo gene birth remains poorly understood, mainly because translation of sequences devoid of genes, or 'non-genic' sequences, is expected to produce insignificant polypeptides rather than proteins with specific biological functions. Here we formalize an evolutionary model according to which functional genes evolve de novo through transitory proto-genes generated by widespread translational activity in non-genic sequences. Testing this model at the genome scale in Saccharomyces cerevisiae, we detect translation of hundreds of short species-specific open reading frames (ORFs) located in non-genic sequences. These translation events seem to provide adaptive potential, as suggested by their differential regulation upon stress and by signatures of retention by natural selection. In line with our model, we establish that S. cerevisiae ORFs can be placed within an evolutionary continuum ranging from non-genic sequences to genes. We identify ~1,900 candidate proto-genes among S. cerevisiae ORFs and find that de novo gene birth from such a reservoir may be more prevalent than sporadic gene duplication. Our work illustrates that evolution exploits seemingly dispensable sequences to generate adaptive functional innovation.
Project description:BackgroundCleidocranial dysplasia (CCD) is a rare genetic disorder affecting bone and cartilage development. Clinical features of CCD comprise short stature, delayed ossification of craniofacial structures with numerous Wormian bones, underdeveloped or aplastic clavicles and multiple dental anomalies. Several studies have revealed that CCD development is strongly linked with different mutations in runt-related transcription factor 2 (RUNX2) gene.ObjectiveIdentification and functional characterization of RUNX2 mutation associated with CCD.MethodsWe performed genetic testing of a patient with CCD using whole exome sequencing and found a novel RUNX2 frameshift mutation: c.1550delT in a sporadic case. We also compared the functional activity of the mutant and wild-type RUNX2 through immunofluorescence microscopy and osteocalcin promoter luciferase assay.ResultsWe found a novel RUNX2 frameshift mutation, c.1550delT (p.Trp518Glyfs*60). Both mutant RUNX2 and wild-type RUNX2 protein were similarly confined in the nuclei. The novel mutation caused abrogative transactivation activity of RUNX2 on osteocalcin promoter.ConclusionsWe explored a novel RUNX2 deletion/frameshift mutation in a sporadic CCD patient. This finding suggests that the VWRPY domain may play a key role in RUNX2 transactivation ability.