[Serological Identification and FUT1 Gene Mutation Analysis of 8 Individuals with Para-Bombay Phenotypes in Guangxi].

OBJECTIVE: To study the serological characteristics and molecular biological basis of 8 individuals with Para-Bombay phenotypes in Guangxi area. METHODS: Serological tests were used to identify the blood groups of red cells. Molecular biological methods, including PCR-SSP for ABO genotyping and DNA sequencing for FUT1, were used to detect the genotypes of ABO and FUT1 which determined the expression of H antigen. RESULTS: Eight individuals in the study were all the Para-Bombay phenotypes, including 4 cases of Bmh and 4 cases of Amh. The DNA sequencing for FUT1 showed that 6 cases were h3h3 [c.658C>T (p.Arg220Cys) homozygous mutation], 1 was h832h832 [c.832G>A (p.Asp278Asn) homozygous mutation], and 1 was h328h3 [compound heterozygous mutations of c.328G>A (p.Ala110Thr) and c.658C>T (p.Arg220Cys)]. CONCLUSION: There are varieties of molecular genetic mechanisms for Para-Bombay phenotypes. In this study, the FUT1 mutations that cause Para-Bombay phenotypes in Guangxi area are mainly h3, h328, and h832, among which h3 is the most common mutant.

[Two Novel Mutations at the CD36 Gene Splicing Sites and Their Molecular Basis for the CD36 Deficiency].

OBJECTIVE: To study two novel CD36 gene mutations at the CD36 splicing sites found in Guangxi population, as well as the molecular basis and population incidence of them. METHODS: DNA sequencing and cDNA clonal sequencing were used to detect CD36 exon sequence and the protein coding region sequence of CD36 mRNA for 2 CD36 deficient individuals (HHC and WGM) found in Guangxi population. Eukaryotic expression cell lines were established for the discovery of CD36 mRNA abnormal transcripts and Western blot assay was used to verify the effect of abnormal CD36 mRNA transcripts on CD36 expression. A DNA PCR-SSP genotyping method was established for the two CD36 novel mutations, and the population distribution was investigated among 110 CD36 deficient individuals in Guangxi region and 296 random individuals in Guangxi population. RESULTS: Novel mutation of c.430 -1G>C was found at the CD36 splicing site in HHC and WGM individuals, and novel mutation of c.1006 +2T>G at the CD36 splicing site was also found in the WGM individual. CD36 cDNA clonal sequencing showed that CD36 c.430 -1G>C could lead to the production of the two CD36 mRNA transcript variants: c.429_430insï¼»430-17_430-2;Cï¼½(p.Ala144fsTer1) and c.430_609del(p.Ala144_Pro203del)(GenBank:HM 217023.1); and CD36 c.1006 +2T>G could lead to the production of CD36 mRNA transcript variant of c.819_1006 del (p.Ser274GlufsTer16) (GenBank: HM217025.1). It was verified that all the three transcript variants could lead to CD36 deficiency by establishment of eukaryotic expression cell lines and Western blot assay. A study of the population incidence of two novel CD36 splicing site mutations found showed that in 110 CD36 deficient individuals and in 296 random individuals in Guangxi region, the mutation rate of CD36 c.430 -1G>C was 10.91% (12/110) and 1.35% (4/296), respectively, while CD36 c.1006 +2T>G was 2.73% (3/110) and 0 (0/296), respectively. CONCLUSION: This study identifies two novel CD36 mutations at CD36 splicing site, and preliminary clarified their molecular basis for the CD36 deficiency and the distribution characteristics in Guangxi population as well. It provides an experimental and theoretical basis for studying the molecular mechanism and characteristics of CD36 deficiency in Chinese population.

[Polymorphism of HLA-A, -B, -C, -DRB1 and -DQB1 Allele and Haplotype Frequency at High Resolution in Guangxi Zhuang Population].

OBJECTIVE: To analyze the characteristics of allelic and haplotypic polymorphisms of human leukocyte antigens at HLA-A, -B, -C, DRB1 and DQB1 loci in Guangxi Zhuang population. METHODS: Polymerase chain reaction-sequence based typing (PCR-SBT) was used to detect. The five loci (HLA-A, -B, -C, -DRB1, -DQB1) in 350 unrelated Zhuang ethnic individual from Guangxi region. Allelic and haplotypic frequencies were calculated by using Arlequin software 3.5.2.2. Phylogeny tree were constructed by using MEGA software 6.0, and SPSS software was used for principal component analysis. RESULTS: Among the five loci in the population, only HLA-A and DRB1 loci were observed as departures from Hardy-Weinberg expectations. A total of 19 HLA-A, 42 HLA-B, 22 HLA-C, 25 HLA-DRB1 and 15 HLA-DQB1 alleles were found in 350 samples. The most highest frequent alleles were A*11: 01(28.57%), B*46: 01(14.00%), C*01: 02(18.43%), DRB1*16: 02 (15.71%）and DQB1*05: 02 (35.00%) . The most common five loci haplotype was A*33: 03-C*03: 02-B*58: 01-DRB1*03: 01-DQB1*02: 01（6.86%）. The phylogenetic tree analysis showed that Guangxi Zhuang population had a relative close genetic relationship with southern Han Chinese populations. CONCLUSION: This reaserch found that the HLA-A, B, C, DRB1 and DQB1 loci are highly polymorphic in Guangxi Zhuang population.

Allelic and haplotype diversity of HLA-A, HLA-B and HLA-DRB1 gene at high resolution in the Nanning Han population.

The distribution of human leucocyte antigen (HLA) allele and haplotype varied among different ethnic populations. In this study, we investigated the allele and haplotype frequencies of HLA-A, HLA-B and HLA-DRB1 loci in the Nanning Han population who live in Guangxi province of China. We identified 26 HLA-A, 56 HLA-B and 31 HLA-DRB1 alleles in 562 Nanning individuals of Han ethnic group by sequence-based typing method. Of these, the three most common alleles in HLA-A, HLA-B and HLA-DRB1 loci, respectively, were A*11:01 (32.12%), A*02:07 (12.54%), A*24:02 (12.01%); B*46:01 (14.41%), B*15:02 (13.61%), B*40:01 (11.48%); DRB1*15:01 (14.15%), DRB1*16:02 (11.57%) and DRB1*12:02 (10.14%). With the exception of HLA-DRB1, the p values of the HLA-A and HLA-B loci showed that the HLA allelic distribution in this population was in accordance with Hardy-Weinberg expectation (p > 0.05). A total of 173 HLA~A-B~DRB1 haplotype with a frequency of >0.1% were presented and the three most common haplotype were HLA-A*33:03~B*58:01~DRB1*03:01 (6.12%), HLA-A*11:01~B*15:02~DRB1*12:02 (3.39%) and HLA-A*11:01~B*15:02~DRB1*15:01 (3.22%). The phylogenetic tree and the principal component analysis suggested that Nanning Han population had a relative close genetic relationship with Chinese Zhuang population and a relative distant genetic relationship with Northern Han Chinese. The information will be useful for anthropological studies, for HLA matching in transplantation and disease association studies in the Chinese population.