Microsatellite variation within the human RHCE gene

Background and Objectives: This study provides a unique method for identify ing individuals carrying the Rh haplotype cDe, and supports a model for the evolution of Rh haplotypes in which cDe is the progenitor. Materials and M ethods: DNA from 212 unrelated donors of known Rh serological phenotype was PCR amplified. The resulting products were analysed by denaturing polyacry lamide gel electrophoresis, denaturing gradient gel electrophoresis and DNA sequencing. Results: Two adjacent microsatellite repeat elements of the fo rm (AC)n (GCAC)n were found within the human Rh blood group genes. These di splay copy number variation which was non-randomly distributed with respect to Rh serological phenotype, and was restricted to alleles of RHCE express ing the c antigen. Conclusion: The predominantly Black African allele cDe d isplayed a unique set of microsatellite alleles, providing a method of iden tifying individuals carrying this haplotype.