Meta-Analysis of Mutations in ALOX12B or ALOXE3 Identified in a Large Cohort of 224 Patients

The autosomal recessive congenital ichthyoses (ARCI) are a nonsyndromic group of cornification disorders that includes lamellar ichthyosis, congenital ichthyosiform erythroderma, and harlequin ichthyosis. To date mutations in ten genes have been identified to cause ARCI: , , , , , , , , , and . The main focus of this report is the mutational spectrum of the genes and , which encode the epidermal lipoxygenases arachidonate 12-lipoxygenase, i.e., 12R type (12R-LOX), and the epidermis-type lipoxygenase-3 (eLOX3), respectively. Deficiency of 12R-LOX and eLOX3 disrupts the epidermal barrier function and leads to an abnormal epidermal differentiation. The type and the position of the mutations may influence the ARCI phenotype; most patients present with a mild erythrodermic ichthyosis, and only few individuals show severe erythroderma. To date, 88 pathogenic mutations in and 27 pathogenic mutations in have been reported in the literature. Here, we presented a large cohort of 224 genetically characterized ARCI patients who carried mutations in these genes. We added 74 novel mutations in and 25 novel mutations in . We investigated the spectrum of mutations in and in our cohort and additionally in the published mutations, the distribution of these mutations within the gene and gene domains, and potential hotspots and recurrent mutations.