Limited genetic information is available concerning the polymorphisms of HIV-1 resistant genes in indigenous Chinese populations. The aim of this study is to identify the allelic frequencies of the chemokine and chemo...Limited genetic information is available concerning the polymorphisms of HIV-1 resistant genes in indigenous Chinese populations. The aim of this study is to identify the allelic frequencies of the chemokine and chemokine receptor genes in the Chinese mainland. Genomic DNA samples extracted from whole blood of 2318 subjects were analyzed by using PCR or PCR/restriction fragment length polymorphism (RFLP) assays, and further confirmed by direct DNA sequencing. Higher frequencies of mutant CCR2-64I (19.15%-28.79%) and SDF1-3’A (19.10% -29.86%) alleles were found in subjects of 8 ethnic groups in the Chinese mainland. In contrast, the △32 mutation in CCRS gene occurs at a very low frequency (0.0016, n=1287) in Han population. A relatively high frequency of CCR5-wt/△32 heterozygotes was observed in Uygurian and Mongolian populations. No A32 mutation allele was detected in Tibetan and other 4 ethnic groups in Yunnan Province. There was no CCR5-m303 mutation in subjects of any ethnic group in the Chinese展开更多
Objective: The aim in this study was to identify the allelicfrequencies of the chemokine (SDF1-3'A) and chemokinereceptor (CCR5△32, CCR5m303 and CCR2-64I) genesresistant to HIV-1 infection and/or disease progress...Objective: The aim in this study was to identify the allelicfrequencies of the chemokine (SDF1-3'A) and chemokinereceptor (CCR5△32, CCR5m303 and CCR2-64I) genesresistant to HIV-1 infection and/or disease progression inindigenous Chinese populations. Methods: By using QIAamp DNA Blood Mini Kit, thegenomic DNA samples were purified from whole peripheralblood of healthy individuals (n=2067) from Han, Uygur,Mongolian and Tibetan ethnic groups, as well as Han patientsincluding HIV-1 carriers (n=330), patients with other sexuallytransmitted diseases (STDs, n=259) and intravenous drugusers (IVDUs, n=125). The allelic polymorphisms wereidentified by means of PCR or PCR-RFLP analyses. Thesequences of randomly selected amplified PCR products werefurther confirmed by direct DNA sequencing. Results: The mutant frequencies were identified to be0%~3.48% for CCR5△32, 0% for CCR5m303,19.15%~28.79% for CCR2-64 and 19.10%~28.73% for SDF1-3'A alleles, respectively, in Chinese healthy individuals fromfour ethnic groups. Our findings indicated the allelicfrequencies vary among the different ethnic groups.Furthermore, the HIV-1 carriers, STD cases and IVDUs (all ofHan ethnicity) were found to have the allelic frequencies of0%~0.19% (CCR5△32), 0% (CCR5m303), 19.31%~20.45%(CCR2-64) and 25.61%~26.83% (SDF1-3'A) with minorvariations in their frequencies between the patients andhealthy Han groups. There was no CCR5-m303 mutationfound in any subject in this study. Conclusion: The examined subjects of four Chinese ethnicorigins showed lower frequencies of CCR5△32 andCCR5m303 alleles, but higher frequencies of mutant CCR2-64I and SDF1-3'A alleles compared to those identified innorthern-European and American Caucasians. Thesignificance of the different frequencies and polymorphisms ofthe above alleles in Chinese populations needs to be furtherexamined in HIV-1/AIDS diseases.展开更多
Knowledge of allelic frequencies at loci associated with kernel weight and effects on kernel weight-related traits is crucial for yield improvement in wheat. Kernel weight-related traits were evaluated in 200 Chinese ...Knowledge of allelic frequencies at loci associated with kernel weight and effects on kernel weight-related traits is crucial for yield improvement in wheat. Kernel weight-related traits were evaluated in 200 Chinese winter wheat cultivars(lines) grown at the Xinxiang Experimental Station, Chinese Academy of Agricultural Sciences, Xinxiang in Henan Province, for three consecutive years from 2014 to 2016. Alleles associated with kernel weight at nine loci, TaCKX6-D1, TaCwi-A1, TaCWI-4A, TaGS1a, TaGS5-A1, TaGS3-3A, TaGW2-6A, TaSus2-2B, and TaTGW6-A1, were determined for all cultivars(lines). ANOVA showed that genotypes, years and their interactions had significant effects on thousand-kernel weight(TKW), kernel length(KL) and kernel width(KW). The overall mean frequencies of alleles conferring high and low TKW at the nine loci were 65.9% and 33.4%, with the ranges of 37.0%–85.0% and 13.5%–63.0% for single loci. The frequencies of high-TKW alleles were over 50.0% at eight of the loci. Genotypes at each locus with the high-TKW allele had higher TKW than those with the low-TKW allele. The high-TKW allele Hap-H at the TaSus2-2B locus can be preferably used to increase grain yield due to its high TKW(49.32 g). A total of 18 main allelic combinations(ACs) at nine loci were detected. Three ACs(AC1–AC3) had significantly higher TKW than AC6 with high-TKW alleles at all nine loci even though they contained some low-TKW alleles. This indicated that other loci controlling kernel weight were present in the high-TKW cultivars. This work provides important information for parental selection and marker-assisted selection for breeding.展开更多
A collection of 167 Thai and exotic rice accessions was subjected for evaluation of genetic diversity and assessment of relationship by simple sequence repeat (SSR) markers. Among a total of 49 SSR markers, 13 markers...A collection of 167 Thai and exotic rice accessions was subjected for evaluation of genetic diversity and assessment of relationship by simple sequence repeat (SSR) markers. Among a total of 49 SSR markers, 13 markers distributing over 12 rice chromosomes showed clear polymorphic band patterns, and they were selected for genetic assessment. A total of 110 alleles were detected with an average of 8.46 alleles per locus. The averages of gene diversity, heterozygosity and polymorphic information content were 0.59, 0.02 and 0.56, respectively. The unweighted-pair group method with arithmetic averages (UPGMA) clustering analysis was performed for genetic distance, and phylogenetic tree was constructed. The result showed that this rice collection was divided into two major groups, classified as japonica and indica subspecies. Within the japonica group, temperate japonica and tropical japonica subgroups can be clearly separated. Three-dimensional principal component analysis projection and model-based population structure analysis showed consistent clustering results with two major groups of UPGMA analysis, supporting the classification of japonica and indica subspecies. The indica allelic frequency was also investigated to provide an indicative guide for breeders to overcome the practical problems on sterility of inter-subspecies hybrid offspring. This rice collection and information obtained in this study will be useful for rice breeding programs.展开更多
文摘Limited genetic information is available concerning the polymorphisms of HIV-1 resistant genes in indigenous Chinese populations. The aim of this study is to identify the allelic frequencies of the chemokine and chemokine receptor genes in the Chinese mainland. Genomic DNA samples extracted from whole blood of 2318 subjects were analyzed by using PCR or PCR/restriction fragment length polymorphism (RFLP) assays, and further confirmed by direct DNA sequencing. Higher frequencies of mutant CCR2-64I (19.15%-28.79%) and SDF1-3’A (19.10% -29.86%) alleles were found in subjects of 8 ethnic groups in the Chinese mainland. In contrast, the △32 mutation in CCRS gene occurs at a very low frequency (0.0016, n=1287) in Han population. A relatively high frequency of CCR5-wt/△32 heterozygotes was observed in Uygurian and Mongolian populations. No A32 mutation allele was detected in Tibetan and other 4 ethnic groups in Yunnan Province. There was no CCR5-m303 mutation in subjects of any ethnic group in the Chinese
基金This project was supported by grant from National Natural Sciences Foundation of the PR China(39770683)
文摘Objective: The aim in this study was to identify the allelicfrequencies of the chemokine (SDF1-3'A) and chemokinereceptor (CCR5△32, CCR5m303 and CCR2-64I) genesresistant to HIV-1 infection and/or disease progression inindigenous Chinese populations. Methods: By using QIAamp DNA Blood Mini Kit, thegenomic DNA samples were purified from whole peripheralblood of healthy individuals (n=2067) from Han, Uygur,Mongolian and Tibetan ethnic groups, as well as Han patientsincluding HIV-1 carriers (n=330), patients with other sexuallytransmitted diseases (STDs, n=259) and intravenous drugusers (IVDUs, n=125). The allelic polymorphisms wereidentified by means of PCR or PCR-RFLP analyses. Thesequences of randomly selected amplified PCR products werefurther confirmed by direct DNA sequencing. Results: The mutant frequencies were identified to be0%~3.48% for CCR5△32, 0% for CCR5m303,19.15%~28.79% for CCR2-64 and 19.10%~28.73% for SDF1-3'A alleles, respectively, in Chinese healthy individuals fromfour ethnic groups. Our findings indicated the allelicfrequencies vary among the different ethnic groups.Furthermore, the HIV-1 carriers, STD cases and IVDUs (all ofHan ethnicity) were found to have the allelic frequencies of0%~0.19% (CCR5△32), 0% (CCR5m303), 19.31%~20.45%(CCR2-64) and 25.61%~26.83% (SDF1-3'A) with minorvariations in their frequencies between the patients andhealthy Han groups. There was no CCR5-m303 mutationfound in any subject in this study. Conclusion: The examined subjects of four Chinese ethnicorigins showed lower frequencies of CCR5△32 andCCR5m303 alleles, but higher frequencies of mutant CCR2-64I and SDF1-3'A alleles compared to those identified innorthern-European and American Caucasians. Thesignificance of the different frequencies and polymorphisms ofthe above alleles in Chinese populations needs to be furtherexamined in HIV-1/AIDS diseases.
基金supported by the National Key Research and Development Program of China (2017YFD0101000, 2016YFD0101004)the National Natural Science Foundation of China (31771881, 31401468)the CAAS Innovation Team and the National Engineering Laboratory of Crop Molecular Breeding
文摘Knowledge of allelic frequencies at loci associated with kernel weight and effects on kernel weight-related traits is crucial for yield improvement in wheat. Kernel weight-related traits were evaluated in 200 Chinese winter wheat cultivars(lines) grown at the Xinxiang Experimental Station, Chinese Academy of Agricultural Sciences, Xinxiang in Henan Province, for three consecutive years from 2014 to 2016. Alleles associated with kernel weight at nine loci, TaCKX6-D1, TaCwi-A1, TaCWI-4A, TaGS1a, TaGS5-A1, TaGS3-3A, TaGW2-6A, TaSus2-2B, and TaTGW6-A1, were determined for all cultivars(lines). ANOVA showed that genotypes, years and their interactions had significant effects on thousand-kernel weight(TKW), kernel length(KL) and kernel width(KW). The overall mean frequencies of alleles conferring high and low TKW at the nine loci were 65.9% and 33.4%, with the ranges of 37.0%–85.0% and 13.5%–63.0% for single loci. The frequencies of high-TKW alleles were over 50.0% at eight of the loci. Genotypes at each locus with the high-TKW allele had higher TKW than those with the low-TKW allele. The high-TKW allele Hap-H at the TaSus2-2B locus can be preferably used to increase grain yield due to its high TKW(49.32 g). A total of 18 main allelic combinations(ACs) at nine loci were detected. Three ACs(AC1–AC3) had significantly higher TKW than AC6 with high-TKW alleles at all nine loci even though they contained some low-TKW alleles. This indicated that other loci controlling kernel weight were present in the high-TKW cultivars. This work provides important information for parental selection and marker-assisted selection for breeding.
基金supported by the Center of Excellence on Agricultural Biotechnology,Science and Technology Postgraduate Education and Research Development Office,Office of Higher Education Commission,Ministry of Education(AG-BIO/PERDO-CHE)Agricultural Research Development Agency(ARDA)National Science and Technology Development Agency in Thailand
文摘A collection of 167 Thai and exotic rice accessions was subjected for evaluation of genetic diversity and assessment of relationship by simple sequence repeat (SSR) markers. Among a total of 49 SSR markers, 13 markers distributing over 12 rice chromosomes showed clear polymorphic band patterns, and they were selected for genetic assessment. A total of 110 alleles were detected with an average of 8.46 alleles per locus. The averages of gene diversity, heterozygosity and polymorphic information content were 0.59, 0.02 and 0.56, respectively. The unweighted-pair group method with arithmetic averages (UPGMA) clustering analysis was performed for genetic distance, and phylogenetic tree was constructed. The result showed that this rice collection was divided into two major groups, classified as japonica and indica subspecies. Within the japonica group, temperate japonica and tropical japonica subgroups can be clearly separated. Three-dimensional principal component analysis projection and model-based population structure analysis showed consistent clustering results with two major groups of UPGMA analysis, supporting the classification of japonica and indica subspecies. The indica allelic frequency was also investigated to provide an indicative guide for breeders to overcome the practical problems on sterility of inter-subspecies hybrid offspring. This rice collection and information obtained in this study will be useful for rice breeding programs.