Abca12 gene

The ABCA12 gene on chromosome 2q35 encodes a protein called the ATP-binding cassette (ABC) transporter. This protein is involved in the lipid transport of the lamellar granules to the apical membrane of the keratinocytes in the statum granulosum. It can be assumed that the mutation either via the alteration of the important nucleotide-binding domain or the transmembrane domain of the ABCA12 protein leads to a considerable loss of function of the lipid barrier and thus to the severe ichthyotic condition of the skin.

Recessive nonsense mutations in the ABCA12 gene lead to harlequin ichthyosis (OMIM 242500 ). Less severe missense mutations of the ABCA12 gene lead to a milder variant of this autosomal recessive congenital ichthyosis (OMIM 601277).