Autosomal recessive congenital ichthyosis: CERS3 mutations identified by a next generation sequencing panel targeting ichthyosis genes

Leila Youssefian, Hassan Vahidnezhad, Amir Hossein Saeidian, Soheila Sotoudeh, Hamidreza Mahmoudi, Maryam Daneshpazhooh, Nessa Aghazadeh, Rebecca Adams, Alireza Ghanadan, Sirous Zeinali, Paolo Fortina, Jouni Uitto

There are at least 38 mutant genes known to be associated with the ichthyosis phenotypes, and autosomal recessive congenital ichthyosis (ARCI) is a specific subgroup caused by mutations in 13 different genes. Mutations in some of these genes, such as CERS3 with only two previous reports, are rare. In this study, we identified mutations in candidate genes in consanguineous families with ARCI with a next generation sequencing (NGS) array that incorporates 38 ichthyosis associated genes. We applied this sequencing array to DNA from 140 ichthyosis families with high prevalence of consanguinity. Among these patients we identified six distinct, previously unreported mutations in CERS3 in six Iranian families. These mutations in each family co-segregated with the ichthyosis phenotype. The patients demonstrated collodion membrane at birth, acrogeria, generalized scaling, and hyperlinearity of the palms and soles. The presence of a significant percentage of CERS3 mutations in our cohort depicts a marked difference between the etiology of ichthyoses in genetically poorly characterized regions and well-characterized western populations. Also, it shows that rare alleles are more prevalent in the gene pool of consanguineous populations and emphasizes the importance of these population studies for better understanding of ichthyosis pathogenesis.European Journal of Human Genetics advance online publication, 6 September 2017; doi:10.1038/ejhg.2017.137.