Identification of two novel PNPLA1 mutations in Turkish families with autosomal recessive congenital ichthyosis

Dökmeci-Emre S, Taşkıran ZE, Yüzbaşıoğlu A, Önal G, Akarsu AN, Karaduman A, Özgüç M. Identification of two novel PNPLA1 mutations in Turkish families with autosomal recessive congenital ichthyosis. Turk J Pediatr 2017; 59: 475-482. Autosomal recessive congenital ichthyosis (ARCI) is a group of inherited keratinization disorders that are characterized by abnormal epidermal keratinization. ARCI patients generally represent serious symptoms including collodion baby phenotype accompanied by dehydration, heat loss, electrolytic imbalance, and sepsis. ARCI shows high degree of clinical and genetic heterogeneity. To date, nine genes were shown to be responsible for ARCI phenotype. One of these genes, patatin-like phospholipase domain containing protein-1 (PNPLA1) was suggested to be involved in the synthesis of ω-O-acylceramides related to epidermal cornified lipid envelope organization. In addition to previously reported PNPLA1 mutations, we report two novel PNPLA1 mutations including one novel missense mutation c.335C > A (p.Ser112Tyr) and one novel deletion mutation c.733_735delTAC (p.Tyr245del) in Turkish ARCI patients from unrelated consanguineous families. We also report previously reported missense mutation c.514G > A (p.Asp172Asn) in Turkish ARCI patients. Novel PNPLA1 mutations were shown to be located in the catalytic patatin domain of PNPLA1 gene. Identification of novel mutations in PNPLA1 gene expands the mutational spectrum in the causative gene. Increase in the total number of cases has high diagnostic value in terms of genotype-phenotype correlation in ARCI patients.