The function of ENSG00000179477 (ALOX12B, arachidonate 12-lipoxygenase, 12R type) is as follows. Catalyzes the regio and stereo-specific incorporation of a single molecule of dioxygen into free and esterified polyunsaturated fatty acids generating lipid hydroperoxides that can be further reduced to the corresponding hydroxy species (PubMed:21558561, PubMed:9618483, PubMed:9837935). In the skin, acts upstream of ALOXE3 on the lineolate moiety of esterified omega-hydroxyacyl-sphingosine (EOS) ceramides to produce an epoxy-ketone derivative, a crucial step in the conjugation of omega-hydroxyceramide to membrane proteins (PubMed:21558561). Therefore plays a crucial role in the synthesis of corneocytes lipid envelope and the establishment of the skin barrier to water loss (PubMed:21558561). May also play a role in the regulation of the expression of airway mucins (PubMed:22441738). {ECO:0000269|PubMed:21558561, ECO:0000269|PubMed:22441738, ECO:0000269|PubMed:9618483, ECO:0000269|PubMed:9837935}.