In a previous investigation, we demonstrated that certain human leukocyte antigens (HLA) may be associated with human immunodeficiency virus type I (HIV-1) infection or protection from infection among regional African Americans and Caucasians. We demonstrated that HLA-DQB1*0605 was associated with a possible increased risk of susceptibility to infection in African Americans and that DQB1*0602 was associated with a possible increased risk of infection in Caucasians. The present study was designed to demonstrate possible HLA associations with HIV-1 disease progression and AIDS in regional African American and Caucasian populations. To differentiate rapid from slow progressors, immune parameters of the HIV-1-positive patient population were monitored over a mean follow-up period of 23 +/- 2 months for African Americans (n = 30) and 25 +/- 5 months for Caucasians (n = 22). To determine significance, HLA allele frequencies among rapid progressors were compared to those of slow progressors, separated by race. Results were analyzed by chi 2 analysis, with Fisher's exact test where applicable, linear logistic regression and Kaplan-Meier survival analysis. In the HIV-1-positive African American group, a better prognosis was associated with HLA-DQB1*0602. In the HIV-1-positive Caucasian group, HLA-DQB1*0302 was associated with rapid HIV disease progression, but no marker was associated with a more favorable prognosis.