Review Article
Yasuyuki Sumikawa, Hitoshi
Abstract
Background: The type of earwax-wet or dry-is determined by a single nucleotide polymorphism (SNP)-538G>A (Gly180Arg)-in the ABCC gene (ABCC11), which encodes an ATP-binding cassette domain. Since axillary osmidrosis is closely related to earwax type, some dermatoses may be associated with earwax type. Objectives: We analyzed the association between the prevalence of a series of dermatoses and earwax phenotype. Further, we investigated ABCC11 localization in the skin. Methods: A total of 660 patients who visited Nopporo Dermatology Clinic in Hokkaido were enrolled in this study. The patients were interviewed to determine their earwax type-wet or dry-and a medical practitioner diagnosed dermatoses. The association between the prevalence of dermatoses and earwax type was analyzed statistically. ABCC11 localization in the skin was immunohistochemically evaluated using anti-ABCC11 antibody. Results: Wet earwax type was more prevalent in patients with acne than in those without acne and the odds ratio was 5.36. On the other hand, dry earwax was more prevalent in patients with atopic dermatitis than in those without it, and the odds ratio was 1.86, which was non-significant. In the immunohistochemical staining, ABCC11 was found to be strongly expressed in the sebaceous glands of wet earwax type skin specimen. Conclusion: Wet earwax phenotype is a high-risk factor for acne. Therefore, hyper-secretion of lipids from sebaceous glands elicited by ABCC11 may play an important role in the pathogenesis of acne.