BTNL2 and sarcoidosis: Importantly, significant progress has been made in identifying genetic variants that contribute to the development of sarcoidosis and complicated sarcoidosis [24, 25] including SNPs in the butyrophillin-like 2 gene (BTNL2), a member of the B7 costimulatory receptor family [26, 27]; and in annexin A11 (ANXA11), a calcium-dependent phospholipid-binding protein involved in cell division and vesicle trafficking [28] which can influence granuloma formation and maintenance [29].