Microsatellite variation within the human RHCE gene
T J Kemp1, M Poulter, B Carritt
1MRC Human Biochemical Genetics Unit, University College London, London, UK. tkemp@hgmp.mrc.ac.uk
Vox Sanguinis
|November 5, 1999
Summary
Researchers identified a unique genetic marker within Rh blood group genes to detect the cDe haplotype, common in Black African populations. This finding aids in understanding Rh haplotype evolution and offers a new identification method.
Area of Science:
- Genetics
- Molecular Biology
- Population Genetics
Background:
- The Rh blood group system is crucial in transfusion medicine and understanding human population genetics.
- The Rh haplotype cDe is prevalent in Black African populations, but its genetic basis and evolutionary origins are not fully understood.
Purpose of the Study:
- To develop a novel method for identifying individuals who carry the Rh haplotype cDe.
- To investigate the evolutionary model of Rh haplotypes, proposing cDe as the progenitor.
Main Methods:
- DNA samples from 212 donors with known Rh serological phenotypes were analyzed.
- Polymerase Chain Reaction (PCR) amplification followed by denaturing polyacrylamide gel electrophoresis (DPAGE), denaturing gradient gel electrophoresis (DGGE), and DNA sequencing were employed.
Main Results:
- Two adjacent microsatellite repeat elements, (AC)n and (GCAC)n, were discovered within the human Rh blood group genes.
- Copy number variation in these microsatellites was observed, showing a non-random distribution linked to Rh serological phenotype.
- This variation was specifically found in alleles of RHCE that express the c antigen.
Conclusions:
- The predominantly Black African allele cDe exhibits a distinct set of microsatellite alleles.
- This unique microsatellite signature provides a reliable method for identifying individuals carrying the cDe haplotype.
- The findings support a model where cDe is the ancestral Rh haplotype, contributing to evolutionary insights.
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