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Background and Objectives Gene conversion events between GYPA and GYPB or GYPA and GYPE are facilitated by the close chromosomal proximity and high degree of sequence homology and can lead to the formation of GP hybrid genes. Discrepant results between blood group genotyping and haemagglutination in 22 random blood donors induced molecular characterization. Materials and Methods Sequence analysis of GYPA exons 1-7 and GYPB exons 1-5 was performed for g DNA and c DNA. The linkage of the nucleotide alterations was defined by haplotype separation. Results DNA analysis demonstrated a normal GYPA haplotype ( GYPA* N n = 20, GYPA* M n = 2) with an altered GP hybrid nucleotide sequence in trans. A GYPB homologue sequence of minimal 10-bp encompassing intron 1 and exon 2 was translated into GYPA, accounting for an amino acid substitution from arginine to glutamic acid at position 13 (38 C>A). Genomic DNA analysis demonstrated the cis-linkage of the hybrid nucleotide sequence with each GYPA( Ser20, Gly24) ( n = 20) associated with the expression of M and GYPA( Leu20, Glu24) ( n = 2) encoding the N phenotype. The serologic data indicate that the changes do not affect the expression of a normal M and N antigen. c DNA sequences confirmed the g DNA results and furthermore identified a heterozygous deletion of GYPB exon 2 in all probands. Conclusion The results document a GYPA- B- A hybrid gene, probably produced via a single unequal homologous recombination event. A segmental transfer of GYPB seems most likely accounting for the allelic dropout. [ABSTRACT FROM AUTHOR]

Background and Objectives The application of a commercial available microcolumn system for ABO/RH determination lead to irregular results in CDE typing of seemingly D- blood samples. In this study, we introduce a comprehensive serological and molecular work-up of a novel haplotype carrying the RHD*weak 4.3 in combination with an aberrant RHCE*ce. Materials and Methods The molecular background was characterized by RHD and RHCE-specific DNA sequencing, RHD cDNA sequencing and RHD zygosity testing. Haplotype-specific extraction and inheritance analysis were initiated to determine the linkage of the polymorphisms. The genetic admixture was studied by whole genome SNP array analysis. Serology was done using commercial available standard techniques and by in-house sera likewise. Results All samples ( n = 29) were shown to harbour an altered RHD(T201R, F223V, P291R) allele known as RHD*weak 4.3 associated with a RHCE*ce(W16C, A36T, L245V) gene formation, expressing CX and VS. Both anti-CX and anti-V/VS were detected as contaminating antibodies in a commercial available microcolumn system for ABO/RH determination accounting for the positive results in CDE typing. Compared with other population data, the samples were clearly identified as Caucasian. Conclusion The RHD*weak 4.3 allele with markedly reduced antigen D expression was shown to be associated with an altered RHCE gene formation leading to the expression of CX and VS. Its frequency was estimated 1 in 854 among apparently D- Upper Austrian blood donors. [ABSTRACT FROM AUTHOR]

Human leukocyte antigen (HLA)-Cw*0740 differs from HLA-Cw*070101 by one nucleotide substitution at codon 73 (GCT>ACT). [ABSTRACT FROM AUTHOR]

HLA-A*33:47 has a single nucleotide difference to A*33:03:01 at position 181, G > C, in exon 2. [ABSTRACT FROM AUTHOR]

We describe the identification of a new DRB1*13 allele, DRB1*1357*, found in two Austrian Caucasian individuals. The novel allele was initially suspected because analysis with sequence-specific primers resulted in an unusual pattern of amplification. Thereafter, exon 2 was further characterized by sequence-based typing. The nucleotide sequence of DRB1*1357 is identical to DRB1*1319 except for a single substitution in codon 47 (TAC to TTC) leading to a change from phenylalanine to tyrosine. [ABSTRACT FROM AUTHOR]