In addition to these statistically significant 10- to 20-fold increases in mRNA expression, there were clear upward trends in expression of HLA-DRB1 and -DQB1 mRNA in B cells from PD GG patients and HLA-DRB1 mRNA expression in monocytes from CTRL GG subjects. The gene discussed is HLA-DRB1; the disease is Parkinson disease.