BTNL2 and sarcoidosis: However, in a number of other diseases, such as ulcerative colitis, multiple sclerosis, type 1 diabetes, rheumatoid arthritis, systemic lupus erythematosus, Graves’ disease, tuberculosis, leprosy, Crohn’s disease as well as in a study of sarcoidosis, the BTNL2 association appears to be “driven” by various HLA-DRB1 alleles in LD with the non-functional rs2076530 A allele [50-54], highlighting the difficulty in identifying the precise risk locus/i when HLA genes and nearby loci in LD are considered simultaneously.