Case Report: De novo KLHL24 Gene Pathogenic Variants in Chinese Twin Boys With Epidermolysis Bullosa Simplex

Syndromic epidermolysis bullosa simplex subtype due to mutations in the KLHL24 gene: series of case reports in Russian families

Objective

Epidermolysis bullosa simplex (EBS) is a common, well-characterized type of epidermolysis bullosa. However, some rare syndromic EBS phenotypes are not well described. The accumulation of clinical descriptions of patients with syndromic subtypes of EBS is important for understanding the natural history of the disease and assessing genotype-phenotype correlations.

Case summary

We present a series of case reports of the syndromic subtype of EBS associated with mutations in the KLHL24 gene in seven patients from four unrelated families. The clinical features of this rare phenotype in children and adult patients are described in detail. In two families, we revealed pathogenic variant c.1A > G (p.Met1?) in the KLHL24 gene. The third family had c.3G > A (p.Met1?) mutation, and the fourth family had a novel de novo variant c.23del (p.Arg8AsnfsTer2).

Conclusion

The description of the clinical manifestations of the disease in two generations of EBS families with different genetic variants allows the assessment and prediction of the natural course and severity of the disease in these families, the risk of complications, and the planning of the amount of medical care necessary.

A de novo start-loss in EFTUD2 associated with mandibulofacial dysostosis with microcephaly: case report

Mandibulofacial dysostosis with microcephaly (MFDM) is a rare genetic disorder inherited in an autosomal dominant pattern. Major characteristics include developmental delay, craniofacial malformations such as malar and mandibular hypoplasia, and ear anomalies. Here, we report a 4.5-yr-old female patient with symptoms fitting MFDM. Using whole-genome sequencing, we identified a de novo start-codon loss (c.3G > T) in the EFTUD2. We examined EFTUD2 expression in the patient by RNA sequencing and observed a notable functional consequence of the variant on gene expression in the patient. We identified a novel variant for the development of MFDM in humans. To the best of our knowledge, this is the first report of a start-codon loss in EFTUD2 associated with MFDM.