Arachidonate-12-Lipoxygenase, 12R Type (ALOX12B)

12R-lipoxygenase catalyzes the conversion of arachidonic acid to 12R-hydroxyeicosatetraenoic acid (12R-HETE). The ALOX12B cDNA showed the greatest sequence similarity to the second type of human 15S-lipoxygenase (ALOX15B), and was more distantly related to human 12S-lipoxygenase (ALOX12). The 2 are coexpressed in tissues, and either gene can be the site of mutations causing NCIE, indicating a functional relationship. Nonbullous congenital ichthyosiform erythroderma (NCIE) is a nonsyndromic form of autosomal recessive congenital ichthyosis characterized by hyperkeratosis and a disruption in the epidermal permeability barrier. Identification of mutations in two lipoxygenases (LOXs), ALOX12B (12R-LOX) and ALOXE3 (eLOX3), and further functional studies implicate ALOX12B and ALOXE3 in the etiology of NCIE.