Exome Profiling Suggests Combined Effect of Myeloperoxidase, Toll-Like Receptors, and Metallopeptidase in Hidradenitis Suppurativa

Background: Hidradenitis suppurativa, also called acne inversa, is a chronic skin inflammatory condition involving hair follicles, sebaceous glands, and apocrine glands. Symptoms can be variable in intensity, ranging from mild to severe. The exact causes of hidradenitis suppurativa are not fully understood, but the etiology is presumed to be multifactorial, encompassing genetics and environmental factors. Methods: Two families presented with hidradenitis suppurativa with an autosomal dominant pattern. We performed whole-exome sequencing in two unrelated patients from the two families. Results: We identified two and three variants in the two families, respectively. Variants involved the TLR2 and MPO genes in the first family and the MMP2, GJB2, and TLR4 genes, some of which have already been previously reported as possible candidates for hidradenitis suppurativa. Conclusion: It is very likely that variants in a single gene only rarely cause the condition and that most cases, especially familial hidradenitis suppurativa cases, may more probably take the form of polygenic disorders.