In a sample of 228 Framingham Study participants aged 58 to 86 who were typed for HLA, neither frequencies of individual antigens nor heterozygosity at the A or B loci appeared to be related to age. Previously found associations could be chance occurrences, or HLA-related effects on longevity in the general population might be small. It is also possible that such effects occur at younger ages than those included in our study or that HLA is related to the aging process in a way that is detectable only at very advanced ages.