AbstractThe distribution of two heavy chain subgroups, VHa and VHy, on rabbit peripheral blood lymphocytes was examined by double membrane immunofluorescence. Fluorescent anti‐a 1 and anti‐y 33 were found to react with separate B cell populations; no doubly stained cells were observed. Further evidence for the independent expression of genes controlling the VHa and VHy subgroups was obtained by neonatal suppression of a 2 or y 33 in a2y33/a3y−heterozygous rabbits. Suppression of VHa did not affect the expression of VHy, nor did the suppression of VHy affect the expression of VHa. The expression of a single VHgene per B cell is in marked contrast to the simultaneous expression of multiple CH