Random survey for RHD alleles among D positive Europeans
Auch gedruckt in der BibliothekZ: J-H 10.605 ; W: W-H 7.964 ; ZAV: J-H 9.398
Ressourcen- / MedientypDissertation, Text
Datum der Freischaltung2004-12-22
Aberrant RHD alleles are much more frequent in Africans than in Europeans. A comprehensive survey of the variability of RHD alleles among D positive Europeans at the molecular level was lacking. Systematic nucleotide sequencing of any RHD exon was not done before in random donors. We performed a random survey among blood donors in South-Western Germany: 500 samples of Rhesus phenotype ccDee, 250 CcDee and 250 ccDEe. They were tested by PCR-SSP for selected nucleotide variations that are coding for S3C (indicative of weak D type 3); L110P (DVII); A149D (weak D type 5); N152T; T201R and F223V (weak D type 4); V270G (weak D type 1); T283I (DHMi); M295I (weak D type 11); G355S (DNB); T379M (DAU-0); and G385A (weak D type 2). All PCR-SSP positive samples were confirmed by nucleotide sequencing of the ten RHD exons from genomic DNA. The nucleotide sequence for RHD exon 5 was tested in all 1000 samples. In the ccDee phenotype, 5 samples were positive for weak D type 4.0; 3 samples for weak D type 4.1; 5 samples for DAU-0; 1 sample for weak D type 11; 1 sample for DV type 1 + DAU; the molecular basis of the latter sample was determined as RHD(F223V, E233Q, T379M) and dubbed DAU-5. There were 2 DNB in the CcDee samples. No variant RHD allele was found in the ccDEe samples. We determined the population frequency of the detected alleles. Nucleotide sequencing RHD exon 5 revealed three new alleles RHD(G212G), RHD(R234W) and RHD(V245L). There are four known D clusters within the RHD phylogeny: DIVa cluster, weak D type 4 cluster, DAU cluster and Eurasian D cluster. Within the phylogeny of the RHD alleles, there are two known recombination events between the clusters. The recombination between the DIVa cluster and weak D type 4 cluster is represented by the DIII type 5 allele. The recombination between the DIVa cluster and Eurasian D cluster is represented by the DIII type 4 allele. In this study, we found the DAU-5 allele, which represents another example for an allele that was formed by a recombination event. In this case, the DAU-5 represents a recombination between the DAU cluster and Eurasian D cluster. The specific allele of the Eurasian D cluster that is involved in this recombination event was DV type 1. In conclusion, we found 17 variant RHD alleles by a PCR-SSP screen, which are consistent with previous reports. The novel allele RHD(F223V, E233Q, T379M) was dubbed DAU-5 and represented a recombination between two known alleles of the DAU cluster and Eurasian D cluster. By sequencing RHD exon 5 three novel alleles were found. In such a limited screen, we characterized 4 novel RHD alleles: DAU-5, RHD(G212G), RHD(R234W) and RHD(V245L). DAU-5 added to the understanding of the RHD phylogeny. Our approach showed that - even within the European population - the variety of RHD alleles may be larger than anticipated and biologic relevant information may be gleaned from such systematic studies.
LizenzStandard (Fassung vom 03.05.2003)
Freie SchlagwörterAllele prevalence
RBC molecular biology