Intellectual disability is the most common developmental disorder caused by chromosomal aberrations as well as single-nucleotide variants (SNVs) and small insertions/deletions (indels). Here we report identification of a novel, probably pathogenic mutation in the WHSC1 gene in a patient case with phenotype overlapping the features of Wolf-Hirschhorn syndrome. Deletions involving WHSC1 (Wolf-Hirschhorn syndrome candidate 1 gene) were described earlier in patients with Wolf-Hirschhorn syndrome. However, to our knowledge, single-point mutations in WHSC1 associated with any intellectual deficiency syndromes have not been reported. Using whole exome sequencing, we found a de novo nonsense mutation in WHSC1 (c.3412C>T, p.Arg1138Ter, NM_001042424.2) in patient with syndromic intellectual disability. This finding is challenging regarding a possible causative role of WHSC1 in intellectual disability syndromes, specifically Wolf-Hirschhorn syndrome. From the clinical standpoint, our finding suggests that next-generation sequencing along with chromosome microarray analysis (CMA) might be useful in genetic testing for patients with intellectual disability and dysmorphic features.

Transgenerational genomic instability was studied in nonirradiated children born from fathers who were irradiated with low doses of ionizing radiation while working as clean-up workers at the Chernobyl Nuclear Power Plant (liquidators) and nonirradiated mothers from nuclear families. Aberrant cell frequencies (ACFs), chromosomal type aberration frequencies, and chromatid break frequencies (CBFs) in the lymphocytes of fathers-liquidators, and their children were significantly higher when compared with the control group (P < 0.05). Individual ACFs, aberration frequencies, and CBFs were independent of the time between irradiation of the father and conception of the child (1 month to 18 years). Chromosomes were categorized into seven groups (A through G). Analysis of aberrant chromosomes within these groups showed no differences in the average frequency of aberrant chromosomes between children and fathers-liquidators. However, significant differences were observed in the average frequency of aberrant chromosomes in groups A, B, and C between children and mothers in the families of liquidators. These results suggest that low doses of radiation induce genomic instability in fathers. Moreover, low radiation doses might be responsible for individual peculiarities in transgenerational genomic instability in children (as a consequence of response to primary DNA damage). Thus, genomic instability may contribute to increased morbidity over the lifetime of these children.

No abstract

No abstract

The Bardet–Biedl syndrome is a rare autosomal recessive disease of the group of ciliopathies with polymorphic clinical symptoms including the retinal degeneration, obesity, polydactyly, mental retardation, hypogonadism, and renal dysfunction. The Pleiotropic effects are caused by the defects in genes encoding the proteins responsible for the functioning of cilia. The Article addresses the issues of the clinical features, diagnosis, differential diagnosis and treatment of this disease. The clinical case demonstrates the patient with Bardet–Biedl syndrome, manifested by the retinal degeneration, obesity, brachydactylia, syndactyly and clinodactyly, hypogenitalism, mental retardation and concomitant hypothyroidism. As per results of the molecular genetic testing, the child was found having the mutations in exon 2 of BBS10 gene c.271dupT and c.583G> A (p.G180E) in the compound heterozygous condition, inherited from the father and mother, respectively, that are the healthy carriers.