Immunoglobulin lambda light chain orphons on human chromosome 8q11.2.

We have identified two V lambda genes outside the major lambda locus on chromosome 22q11.2, and shown that they reside on chromosome 8q11.2. One gene (Orphée1), hybridizing strongly to the V lambda probes, was sequenced and found to belong to the V lambda 8 family; the other gene (Orphée2) only hybridized weakly. Orphée1 was present in all individuals tested (140) from three different populations, and was also found in gorillas. We envisage that these genes were generated by duplication and translocation of the V lambda 8a gene (and a V lambda pseudogene) from the major locus, and that this event occurred before the evolutionary divergence of humans and gorillas. As there is no other evidence for V lambda genes outside the major locus, it appears that the human lambda locus has undergone considerably less evolutionary shuffling than either the human light chain kappa locus or the heavy chain locus.