Findings from a recent study showed a high heritability among patients with hidradenitis suppurativa (HS), which suggests a stronger genetic basis than previously thought. In addition, the study also supports a multifactorial cause, with environmental factors found to contribute to the susceptibility of HS.
Up to 38% of patients report a family history of HS. “Variations in the γ-secretase genes are found mainly in familial cases with an autosomal dominant pattern of inheritance,” the researchers said. They further noted that the varioations are rare in the general HS population, even in patients who report a family history of the disease.
They assessed the heritability of HS using data from the Netherlands Twin Register from 2011 to 2016. A total of 978 female monozygotic twin pairs, 344 male monozygotic twin pairs, 426 female dizygotic twin pairs, 167 male dizygotic twin pairs, and 428 dizygotic twin pairs of the opposite sex were included in the study. All twin pairs completed questions on HS in the register surveys. Using this data, the proportion of susceptibility to HS due to additive genetic factors (narrow-sense heritability), dominant genetic factors, common or shared environmental factors, or unshared or unique environmental factors were assessed.
Among the twin pairs, the prevalence of HS was 1.2%, the researchers wrote. The narrow-sense heritability of HS was 77% (95% CI, 54%-90%), with the remainder of variance due to unshared or unique environmental factors based on an age-adjusted model combining additive genetic factors and unshared or unique environmental factors, they added.
“The results of this study strongly support the need for a global genome-wide association study in the general population of patients with HS,” the researchers concluded.
van Straalen KR, Prens EP, Willemsen G, Boomsma DI, van der Zee HH. Contribution of genetics to the susceptibility to hidradenitis suppurativa in a large, cross-sectional Dutch twin cohort. JAMA Dermatol. Published online October 14, 2020. doi:10.1001/jamadermatol.2020.3630