HLA-DRW4 in 91% of Jewish pemphigus vulgaris patients.

HLA-DRW4 was found in all 11 female and 10 out of 12 male Jewish patients with pemphigus vulgaris, a frequency of 91% in all, which was significantly higher than the 25% frequency among normal Jewish controls. The relative risk was 31.5. The BW38-DRW4 haplotype occurred in 12 out of 22 patients (55%) but in only 2% of White non-Jews and 11% of normal Jewish people.