In a study designed to confirm our preliminary report of associations between HLA-B12, atopy, and relapse following cyclophosphamide treatment in steroid-responsive nephrotic syndrome (SRNS), we again found a higher incidence of HLA-B12 in SRNS children (44%) than we did in controls (24%). The association of HLA-B12 with short time-to-relapse after cyclophosphamide treatment of SRNS was also confirmed, but that with atopy in SRNS children was not, though we observed a similarly high incidence of atopy in them as before.