The self-incompatibility ( S) loci from the Solanaceae, Rosaceae and Scrophulariaceae encode a class of ribonucleases, known as S RNases, which have been shown to control the pistil expression of self-incompatible rea...The self-incompatibility ( S) loci from the Solanaceae, Rosaceae and Scrophulariaceae encode a class of ribonucleases, known as S RNases, which have been shown to control the pistil expression of self-incompatible reaction. In the former two families, the S loci have been shown to be located near centromere. However, the chromosomal location of the S locus in Antirrhinum, a species of the Scrophulariaceae, is not known. To determine its chromosomal location and genomic organization, an S-2 RNase gene and its corresponding 63 kb BAC clone were separately used for fluorescence in situ hybridization (FISH) of mitotic metaphase chromosomes of a self-incompatible Antirrhinum line Of S2S5. The results showed that the S-2 RNase detected a doublet signal near the centromere of the smallest chromosome (2n = 16). Two separate doublet signals of the tested BAC sequence were shown on both sides of the centromeres of all eight pairs of the chromosomes, suggesting that the Antirrhinum S locus is located in a pericentromeric region. Furthermore, a retrotransposon, named RIS1 (retrotransposon in the S locus), which has not been identified yet in. Antirrhinum, was found next to S-2 RNase. Taken together, the centromeric location of the S locus from the three S-RNase-based self-incompatible families provides a further support on a common origin of their evolution as well as suppressed recombination.展开更多
Objectives To detect the polymorphism of D5S436 locus, and to carry out an amplified fragment length polymorphism (Amp FLP) genotyping linkage analysis in asthma families.Methods Allele and genotype frequencies of ...Objectives To detect the polymorphism of D5S436 locus, and to carry out an amplified fragment length polymorphism (Amp FLP) genotyping linkage analysis in asthma families.Methods Allele and genotype frequencies of the high polymorphic D5S436 locus were determined in 92 unrelated Chinese individuals by using polymerase chain reaction (PCR). The amplified fragments were separated by denaturing polyacrylamide gel electrophoresis and silver staining techniques. Results Eight alleles and 22 genotypes were observed in this population. The heterozygosity was 78.26%. The polymorphism information content (PIC) was 0.76. Amp FLP genotyping linkage analyses were carried out in four asthma families, demonstrating that the locus was inherited according to Mendel's law and had a clear result.Conclusion The PIC of D5S436 is high in Chinese individuals, so it could be used as a genetic marker of asthma in Chinese and might be useful in the gene diagnosis of asthma.展开更多
文摘The self-incompatibility ( S) loci from the Solanaceae, Rosaceae and Scrophulariaceae encode a class of ribonucleases, known as S RNases, which have been shown to control the pistil expression of self-incompatible reaction. In the former two families, the S loci have been shown to be located near centromere. However, the chromosomal location of the S locus in Antirrhinum, a species of the Scrophulariaceae, is not known. To determine its chromosomal location and genomic organization, an S-2 RNase gene and its corresponding 63 kb BAC clone were separately used for fluorescence in situ hybridization (FISH) of mitotic metaphase chromosomes of a self-incompatible Antirrhinum line Of S2S5. The results showed that the S-2 RNase detected a doublet signal near the centromere of the smallest chromosome (2n = 16). Two separate doublet signals of the tested BAC sequence were shown on both sides of the centromeres of all eight pairs of the chromosomes, suggesting that the Antirrhinum S locus is located in a pericentromeric region. Furthermore, a retrotransposon, named RIS1 (retrotransposon in the S locus), which has not been identified yet in. Antirrhinum, was found next to S-2 RNase. Taken together, the centromeric location of the S locus from the three S-RNase-based self-incompatible families provides a further support on a common origin of their evolution as well as suppressed recombination.
文摘Objectives To detect the polymorphism of D5S436 locus, and to carry out an amplified fragment length polymorphism (Amp FLP) genotyping linkage analysis in asthma families.Methods Allele and genotype frequencies of the high polymorphic D5S436 locus were determined in 92 unrelated Chinese individuals by using polymerase chain reaction (PCR). The amplified fragments were separated by denaturing polyacrylamide gel electrophoresis and silver staining techniques. Results Eight alleles and 22 genotypes were observed in this population. The heterozygosity was 78.26%. The polymorphism information content (PIC) was 0.76. Amp FLP genotyping linkage analyses were carried out in four asthma families, demonstrating that the locus was inherited according to Mendel's law and had a clear result.Conclusion The PIC of D5S436 is high in Chinese individuals, so it could be used as a genetic marker of asthma in Chinese and might be useful in the gene diagnosis of asthma.
