The ABCA12 gene encodes for the ATP-binding cassette sub-family A member 12 transporter protein. Transporter proteins carry out the active transportation of various molecules across extra- and intracellular membranes. The ABCA12 protein plays a major role in lipid transport in cells that make up the epidermis. This lipid transport appears to be important for normal development of the skin. Studies on animal models have suggested that the protein plays a critical role in the formation of the skin's permeability barrier via an effect on the generation of a highly specialized class of ceramide esters.
Mutations in ABCA12 have been associated with disruption of the lamellar permeability barrier and skin ichthyoses of variable severity. These include conditions like Ichthyosis, Congenital, Autosomal Recessive 4A and Harlequin Ichthyosis.