Evolution of a group of transposed human V kappa genes

Eleven V kappa genes within a genomic region which has been transposed from the short to the long arm of chromosome 2 have been characterized by sequence analyses. Nine of the analysed genes exist within the genome in three highly homologous copies each. Sequence comparisons of the triplicated genes make it very likely that the three copies of a given gene were produced at different times during evolution. A chain of events which led to a stepwise amplification of precursor genes is discussed.