HLA-DRB1*15021 is the predominant allele in Japanese patients with juvenile dermatomyositis
Tomono, N.; Mori, M.; Nakajima, S.; Miyamae, T.; Ito, S.; Mitsuda, T.; Yokota, S.
Journal of Rheumatology 31(9): 1847-1850
2004
ISSN/ISBN: 0315-162X PMID: 15338511 Document Number: 568200
Objective. To investigate HLA molecules and genes in Japanese patients with juvenile dermatomyositis (JDM). Methods. Twelve patients (8 girls and 4 boys) with ages of onset between 3 and 15 years were included. HLA class I antigen phenotypes were serologically typed by the Terasaki-NIH standard method. DNA was extracted from peripheral blood leukocytes using the phenol-chloroform extraction procedure, and stored at -70degreeC until use. Genomic DNA for HLA-DRB1, HLA-DQA1, and HLA-DQB1 alleles in JDM patients and controls was determined by the direct sequence method. Results. HLA-A24 and B52 were each detected in 7 cases (OR = 0.86, 5.02, p = 0.930, 0.006, respectively). HLA-DRB1*15021 was observed in 7 patients. This was significantly more frequent than occurred in the controls (OR = 5.72, p = 0.002). Seven patients out of 12 (58%) had the combination HLA-B52, DRB1*15021, DQA1*0103, and DQB1*0601. Conclusion. Our results suggest that the susceptibility gene for JDM either is HLA-DRB1*15021 or is present near the HLA-DRB1 locus. This differs from previous reports that describe the association with HLA-DQA1*0501 in Caucasian patients with JDM. The combination HLA-B52, DRB1*15021, DQA1*0103, and DQB1*0601 may contribute to the pathogenesis of JDM in Japanese patients.