ABCA12

ATP-binding cassette sub-family A member 12 also known as ATP-binding cassette transporter 12 is a is_associated_with::protein that in humans is encoded by the ABCA12 is_associated_with::gene.

ABCA12 belongs to a group of genes called the is_associated_with::ATP-binding cassette family, which makes proteins that transport molecules across is_associated_with::cell membranes. The ABCA12 gene is active in some types of is_associated_with::skin cells and in several other tissues, such as is_associated_with::testis, is_associated_with::placenta, is_associated_with::lung, is_associated_with::stomach, and fetal brain and liver. This protein appears to be essential for normal development of the is_associated_with::skin, which provides a barrier between the body and its surrounding environment. It transports is_associated_with::epidermoside, a is_associated_with::glucosylceramide, out of the keratinocytes of the is_associated_with::stratum corneum of the epidermis.

The ABCA12 gene is located on the long (q) arm of chromosome 2 between positions 34 and 35, from is_associated_with::base pair 215,621,772 to base pair 215,828,656.

Related conditions
Several is_associated_with::mutations in the ABCA12 gene are known to cause is_associated_with::harlequin-type ichthyosis. Most of these mutations are predicted to lead to an absence of ABCA12 protein or the production of an extremely small version of the protein that cannot transport lipids properly. A loss of functional ABCA12 protein causes numerous problems with the development of the epidermis before and after birth. Abnormalities in lipid transport prevent the skin from forming an effective barrier and result in the hard, thick scales characteristic of harlequin ichthyosis.

Mutations in the ABCA12 gene also cause another severe skin disorder, is_associated_with::lamellar ichthyosis type 2. People with this disorder have red, scaly, plate-like skin covering most of their bodies. The ABCA12 mutations that cause this disorder substitute one is_associated_with::amino acid (a building block of proteins) for another amino acid in the ABCA12 protein. These mutations almost always occur in an important functional region of the protein (the region that binds to ATP, a molecule that supplies energy for chemical reactions). Changes in the structure of the ABCA12 protein likely disrupt its ability to transport lipids, which affects the development of skin before and after birth.