fA. Fouwen NIAID Raley THE LINDSLEY F KIMBALL RESEARCH INSTITUTE of The New York Blood Center Fred H. Allen Laboratory of Immunogenetics 310 East 67 Street, New York, N.Y. 10021 (212) 570-3230 April 4, 1991 Joshua Lederberg University Professor The Rockefeller University 1230 York Avenue New York, NY 10021-6399 Dear Josh: Thank you ever so much for your note of March gth concerning MHC compatibility and HIV transmission.: I am very much interested! Cladd Stevens and I are currently following a cohort of homosexual men in a Prospective Aids Study (PAS). A few years ago, we. looked at sexual partners of the participants and could find no special association between HLA compatibility and risk of infection. Essentially all the risk was given by the epidemiological exposure, i.e., by risk behavior. However, this population is not appropriate to test for the effects of viruses on the maintenance of MHC polymorphism in the population or its converse, the contribution of the MHC to risk of infection. I should be most interested in a study of transplacental A transmission which is said to occur in less than 1/3 of children from HIV+ mothers. It would be very interesting to discuss a possible collaboration in these studies, within or in addition to PAS. With best regards. MS; mig Pablo Rubinste M.D. ch a Receso fo Director, ‘The Fred H. Allen . Laboratory of Immunogenetics ? > el bra