Advances in the genetics of sarcoidosis.

Sarcoidosis is an uncommon disease of granulomatous inflammation. Genetic predisposition to sarcoidosis is indicated by observations of familial clustering, increased concordance in monozygotic twins over other siblings, and variations in susceptibility and disease presentation among different ethnic groups. Published studies on sarcoidosis have investigated a variety of genetic associations. These studies used techniques ranging from classic human lymphocyte antigen genotype correlations to genome-wide linkage scans. Results have both supported and refuted disease associations with a number of genes potentially involved in the pathogenesis of sarcoidosis. Here, we review representative studies concerning the genetics of sarcoidosis. While investigations to date have failed to identify a unifying genetic signature associated with sarcoidosis, numerous studies have identified genetic associations with disease subtypes or within specific populations. These studies suggest that genetic susceptibility to sarcoidosis is complex and polygenic in nature. Future studies will help clarify the genetics of sarcoidosis and allow for the development of diagnostic, prognostic and therapeutic technologies.