This study was purposed to investigate the molecular polymorphism of gypa gene in association with MN human blood group in Chinese Han population. The MN phenotypes of 202 random samples from unrelated Chinese Han volunteers were identified by serology techniques. The primer for gypa gene exon 2 were designed and synthesized according to reference sequences of NG-007470 gene from GenBank, the DNA of 202 samples was amplified by PCR, at the same time, the amplified products were analyzed by direct DNA sequencing. The results showed that all samples had 2 base substitutions at 1st and 56th nt of gypa exon 2, among them the MN phenotype heterozygote exited mainly in the form of 1A > C, 22T/C, 34A/G, 35T/G, 56T > C; the MM phenotype homozygote exited mainly in the form of 1A > C, 22C, 34G, 35T, 56T > C; the NN phenotype homozygote exited mainly in the form of 1A > C, 22T, 34A, 35G, 56T > C. It is concluded that the polymorphism of gypa gene in associated with MN blood group in Chinese Han population is decided by 5 nucleotide sites of 1, 22, 34, 35 and 56. The bases of 1 and 56 are non-functional gypa single nucleotide polymorphism.
Asian Continental Ancestry Group ; genetics ; Base Sequence ; Exons ; Genotype ; Glycophorin ; genetics ; Humans ; MNSs Blood-Group System ; genetics ; Molecular Sequence Data ; Polymorphism, Genetic ; Sequence Analysis, DNA

OBJECTIVE: To explore the genetic mutation mechanism of a rare Rhesus D variant individual. METHODS: Regular serological assay was used for determination of Rh type for the sample. Indirect anti-human globulin test (IAT) was used to confirm the RhD antigen and screen the antibodies. D-screen reagent was used to analyze the RhD epitopes of the sample. RHD genotype and RHD zygosity testing of the sample were detected by palymerase chain reaction with sequence-specific primers (PCR-SSP). The full length coding region of RHD gene was sequenced. RHD mRNA was detected using reverse transcription polymerase chain reaction (RT-PCR). The PCR products were cloned and sequenced. RESULTS: The RhD blood group of the sample was determined as weak D, and the Rh phenotype was CcDEe. The antibody screening was negative. The sample tested with all monoclonal anti-Ds in D-screen showed the D epitope profiles as partial D types. The analysis of RHD gene sequence indicated that the individual with RHD c.845G/A and RHD c.1227G/A base heterozygosis. Three kinds of alternative splicing isoforms were obtained by TA cloning and sequencing. CONCLUSION The object has RHD c.845G/A and RHD c.1227G/A mutation. This heterozygous mutation is responsible for the low expression of RhD antigen on the red blood cells of the sample.
Alleles ; Blood Group Antigens ; Genotype ; Mutation ; Phenotype ; Polymerase Chain Reaction ; Rh-Hr Blood-Group System/genetics* ; Humans