They share the same IL23R variant (rs117633859), and they are both associated with class II HLA polymorphisms (sarcoidosis: HLA-DRB1*03, *08, *09, *11, *12, *14, and *15; VKH disease: HLA-DRB1*04) as risk factors. This evidence concerns the gene IL23R and Vogt-Koyanagi-Harada disease.