ABCC11

ABCC11, or ATP-binding cassette sub-family C member 11, is a membrane transporter protein of the ATP-binding cassette (ABC) family. It is expressed in various tissues, with notable levels in apocrine glands such as those in the underarm, as well as in breast and placental tissues. The protein functions as an ATP-dependent efflux transporter, moving a range of organic anions and conjugates across cellular membranes.

In apocrine glands, ABCC11 is implicated in the secretion of odorant precursors that contribute to body odor. The volatile compounds responsible for axillary odor, including certain steroids, are believed to be influenced by ABCC11–mediated transport, linking the gene to odor production in humans.

Genetic variation in ABCC11 has been extensively studied, particularly the single-nucleotide polymorphism rs17822931, also known as 538G>A. The A allele is associated with a dry earwax phenotype and substantially reduced axillary odor due to diminished secretion of odorant precursors. The GG genotype is more commonly found in individuals with wet earwax and stronger body odor. Allele frequencies differ among populations, with the A allele being relatively common in East Asian populations compared to European or African populations.

Clinical and evolutionary considerations include the association of ABCC11 variants with earwax type and body odor traits, as well as ongoing research into how these genetic differences influence odor-related biology and human adaptation.

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