AIM:To explore the germline mutations of the two main DNA mismatch repair genes (hMSH2and hMLH1） between patients with hereditary non-polyposis colorectal cancer (HNPCC) and suspected (atypical) HNPCC.METHODS:Genomic...AIM:To explore the germline mutations of the two main DNA mismatch repair genes (hMSH2and hMLH1） between patients with hereditary non-polyposis colorectal cancer (HNPCC) and suspected (atypical) HNPCC.METHODS:Genomic DNA was extracted from the peripheral blood of the index patient of each family,and germline mutations of hMSH2 and hMLH1 genes were detected by PCR-single strand conformation polymorphism (PCR-SSCP) and DNA sequencing techniques.RESULTS:For PCR-SSCP analysis,67% (4/6) abnormal exons mobility in typical group and 33% (2/6) abnormal exons mobility in atypical group were recognized.In direct DNA sequencing,50%(3/6) mutation of MMR genes in typical group and 33% (2/6) mutation of MMR genes in atypical group were found,and 4/6(66.67%) and 1/6(16.67%) mutations of hMSH2 and hMLH1 were identified in typical HNPCC and atypical HNPCC,respectively.CONCLUSION:Mutation detection of the patients is of benefit to the analysis of HNPCC and, PCR-SSCP is an effective strategy to detect the mutations of HNPCC equivalent to direct DNA sequence.It seems that there exist more complicated genetic alterations in Chinese HNPCC patients than in Western countries.展开更多
It reveals that the MHC （major histocompatibility complex） gene product always involved in the control of immune response and disease resistance. Nowadays many studies have indicated the OLA （ovine lymphocyte anti...It reveals that the MHC （major histocompatibility complex） gene product always involved in the control of immune response and disease resistance. Nowadays many studies have indicated the OLA （ovine lymphocyte antigen） DRB1 gene is associated with some sheep diseases. Tibetan sheep is one of the three major shag sheep breeds in China, and also have the largest number of China＇s sheep breeds. But till now no report has been seen on studying DRB1 gene in Tibetan sheep of China. To understand the evolution and provide the basis for sheep disease resistance, polymorphism in the exon2 ofDRB1 gene in Tibetan sheep was analyzed. The PCR-SSCP, cloning and sequencing were used to analyse DRB1 gene variation in 600 Tibetan sheep of China. And the genetic relationship and evolutionary significance of the alleles had also been analyzed. Total of 31 alleles were identified, in which 15 alleles had not been reported before. And there were 70 SNPs （single nucleotide polymorphisms） sites in 31 sheep DRB1 gene haplotypes, the proportion was 29.5% to the whole exort2 sequence. All of this indicated that DRB1 exon2 is highly polymorphic in Tibetan sheep. The variation identified here might have an impact on both the function and level of expression of the OLA-DRB1.展开更多
基金Supported by the National Natural Science Foundation of China,No.30170927
文摘AIM:To explore the germline mutations of the two main DNA mismatch repair genes (hMSH2and hMLH1） between patients with hereditary non-polyposis colorectal cancer (HNPCC) and suspected (atypical) HNPCC.METHODS:Genomic DNA was extracted from the peripheral blood of the index patient of each family,and germline mutations of hMSH2 and hMLH1 genes were detected by PCR-single strand conformation polymorphism (PCR-SSCP) and DNA sequencing techniques.RESULTS:For PCR-SSCP analysis,67% (4/6) abnormal exons mobility in typical group and 33% (2/6) abnormal exons mobility in atypical group were recognized.In direct DNA sequencing,50%(3/6) mutation of MMR genes in typical group and 33% (2/6) mutation of MMR genes in atypical group were found,and 4/6(66.67%) and 1/6(16.67%) mutations of hMSH2 and hMLH1 were identified in typical HNPCC and atypical HNPCC,respectively.CONCLUSION:Mutation detection of the patients is of benefit to the analysis of HNPCC and, PCR-SSCP is an effective strategy to detect the mutations of HNPCC equivalent to direct DNA sequence.It seems that there exist more complicated genetic alterations in Chinese HNPCC patients than in Western countries.
文摘It reveals that the MHC （major histocompatibility complex） gene product always involved in the control of immune response and disease resistance. Nowadays many studies have indicated the OLA （ovine lymphocyte antigen） DRB1 gene is associated with some sheep diseases. Tibetan sheep is one of the three major shag sheep breeds in China, and also have the largest number of China＇s sheep breeds. But till now no report has been seen on studying DRB1 gene in Tibetan sheep of China. To understand the evolution and provide the basis for sheep disease resistance, polymorphism in the exon2 ofDRB1 gene in Tibetan sheep was analyzed. The PCR-SSCP, cloning and sequencing were used to analyse DRB1 gene variation in 600 Tibetan sheep of China. And the genetic relationship and evolutionary significance of the alleles had also been analyzed. Total of 31 alleles were identified, in which 15 alleles had not been reported before. And there were 70 SNPs （single nucleotide polymorphisms） sites in 31 sheep DRB1 gene haplotypes, the proportion was 29.5% to the whole exort2 sequence. All of this indicated that DRB1 exon2 is highly polymorphic in Tibetan sheep. The variation identified here might have an impact on both the function and level of expression of the OLA-DRB1.
