TYK2 and diabetes mellitus: We found Tyk2 gene mutations at the promoter region (−678_−674 5A>5T, −713T>C, −735 C>T, −919 G>T, −938_−930 del 9T, −998 G>C, −1010T>C, −1015 C>T, −1219A>G) from transcription start point at exon 1 and exons 9592A>G and 10642A>G only in virus-induced diabetes-sensitive SJL and SWR mice (Table 1).