Sarcoidosis is a multiple organ immune-mediated disease of unknown aetiology. Identified genetic risk factors within the major histocompatibility complex (MHC), such as butyrophilin-like (BTNL) 2, human leukocyte antigen (HLA)-DRB1* 03 and HLA-DRB1* 15, and protective factors, such as HLA-DRB1* 01, are found in many populations [ 1, 2]. The vast majority of sarcoidosis patients have a favourable prognosis, but approximately 20% develop a chronic, disabling disease [ 3].

Chronic beryllium disease (CBD) and chronic sarcoidosis share similarities as granulomatous diseases and they are pathologically indistinguishable from each other. CBD has been associated with HLA-DPB1* 02: 01, especially with a glutamic acid residue at position 69 (Glu69)[ 4]. A functional splice-site polymorphism rs2076530 within the BTNL2 gene has been suggested to predispose to sarcoidosis [ 5]. However, previous studies have shown conflicting results as to whether HLA-DPB1 also predisposes to sarcoidosis, and whether the BTNL2 association is a result of linkage disequilibrium with HLA-DRB1 [ 6, 7].