A rice male-sterile mutant OsMS-L of japonica cultivar 9522 background, was obtained in M4 population treated with Co γ-Ray. Genetic analysis indicated that the 60 male-sterile phenotype was controlled by a single re...A rice male-sterile mutant OsMS-L of japonica cultivar 9522 background, was obtained in M4 population treated with Co γ-Ray. Genetic analysis indicated that the 60 male-sterile phenotype was controlled by a single recessive gene. Results of tissue section showed that at microspore stage, OsMS-L tapetum was retarded. Then tapetal cells ex- panded and microspores degenerated. No matured pollens were observed in OsMS-L anther locus. To map OsMS-L lo- cus, an F2 population was constructed from the cross be- tween the OsMS-L (japonica) and LongTeFu B(indica). Firstly, the OsMS-L locus was roughly mapped between two SSR markers, RM109 and RM7562 on chromosome 2. And then eleven polymorphic markers were developed for further fine fine-mapping. At last the OsMS-L locus was mapped between the two InDel markers, Lhs10 and Lhs6 with genetic distance of 0.4 cM, respectively. The region was delimited to 133 kb. All these results were useful for further cloning and functional analysis of OsMS-L.展开更多
Well-spread meiotic pachytene bivalents were obtained by using the prolonged hypotonic treatment com-bined with high chloroform Carnory’s fixative solution from cells of the testes of domestic pigs. Comparison in the...Well-spread meiotic pachytene bivalents were obtained by using the prolonged hypotonic treatment com-bined with high chloroform Carnory’s fixative solution from cells of the testes of domestic pigs. Comparison in the division index and length of pachytene bivalents with metaphase chromosomes showed that those of the former are 5 times higher and 3.42(1.87-5.98) times longer than those of the latter. Comparative studies on chromomere maps of bivalents and mitotic chromosomal G-bands were conducted by using the chromo-some 12 as a example. Sex vesicle and various shapes of synaptic sex chromosomes have been observed.Two-color PRimed IN Situ (PRINS) labeling has been conducted successfully on pachytene bivalents of pigs.展开更多
Genetic variations and their functional implications have been one of the focuses in recent genome research. With the release of the HapMap by the International Consortium, and the availability of the ultra-high-volum...Genetic variations and their functional implications have been one of the focuses in recent genome research. With the release of the HapMap by the International Consortium, and the availability of the ultra-high-volume genotyping platform, it will soon be possible to use genome-wide association ap- proach to identify genetic variations responsible for complex traits/diseases. While the power of this ap- proach is generally agreed, it is a debated issue as to how much population difference should be exploited, and how best it should be applied. To address this issue we have sequenced 7 genes in the centromeric region of chromosome 15, investigated their SNPs, SNP frequencies, tagSNPs, LD structures, and hap- lotypes in 50 Tibetan subjects, and compared them with those from the Han population. Genetic diversi- ties between the two populations were also quantified. Our results show that the overall genetic variation between the two populations is very little, but there are differences, primarily in allele frequencies, which is a dominating factor for haplotypes and tagSNPs. In general Tibetans have longer LD and less diversity inthe region studied. These data provide genetic evi- dence for the close relationship between the two populations, and support the idea that all populations are fundamentally the same, but also indicate popu- lation variations, particularly in allele frequency, should be taken into account in complex traits/ dis- eases analysis. Data obtained in this investigation not only help us understand the genome region, but also provide road maps for variation study in the genes/ region in Tibetan population.展开更多
基金This work Was supported by The National Basic Research Program of China(Grant No.TG1999011605)the Shanghai Municipal Committee of Science and Technology(Grant No.03DJ14016).
文摘A rice male-sterile mutant OsMS-L of japonica cultivar 9522 background, was obtained in M4 population treated with Co γ-Ray. Genetic analysis indicated that the 60 male-sterile phenotype was controlled by a single recessive gene. Results of tissue section showed that at microspore stage, OsMS-L tapetum was retarded. Then tapetal cells ex- panded and microspores degenerated. No matured pollens were observed in OsMS-L anther locus. To map OsMS-L lo- cus, an F2 population was constructed from the cross be- tween the OsMS-L (japonica) and LongTeFu B(indica). Firstly, the OsMS-L locus was roughly mapped between two SSR markers, RM109 and RM7562 on chromosome 2. And then eleven polymorphic markers were developed for further fine fine-mapping. At last the OsMS-L locus was mapped between the two InDel markers, Lhs10 and Lhs6 with genetic distance of 0.4 cM, respectively. The region was delimited to 133 kb. All these results were useful for further cloning and functional analysis of OsMS-L.
基金supported by the Key Project of National Basic Research and Developmental Plan(G2000016103)of Chinathe National Outstanding Youth Science Foundation(39925027)+1 种基金National Natural Science Foundation of China(39570519)the International Foundation for Science(IFS,B/2425-2F).
文摘Well-spread meiotic pachytene bivalents were obtained by using the prolonged hypotonic treatment com-bined with high chloroform Carnory’s fixative solution from cells of the testes of domestic pigs. Comparison in the division index and length of pachytene bivalents with metaphase chromosomes showed that those of the former are 5 times higher and 3.42(1.87-5.98) times longer than those of the latter. Comparative studies on chromomere maps of bivalents and mitotic chromosomal G-bands were conducted by using the chromo-some 12 as a example. Sex vesicle and various shapes of synaptic sex chromosomes have been observed.Two-color PRimed IN Situ (PRINS) labeling has been conducted successfully on pachytene bivalents of pigs.
基金supported by the 863 Project(Grant No.2001AA221102)the Natural Science Foundation of Guangdong Province(Grant No.031673)+1 种基金the Guangzhou Municipal Science and Technology Foundation(Grant Nos.2002Z3-C7191&2004Z3-C7501)the China Medical Board of New York(Grant No.01-759).
文摘Genetic variations and their functional implications have been one of the focuses in recent genome research. With the release of the HapMap by the International Consortium, and the availability of the ultra-high-volume genotyping platform, it will soon be possible to use genome-wide association ap- proach to identify genetic variations responsible for complex traits/diseases. While the power of this ap- proach is generally agreed, it is a debated issue as to how much population difference should be exploited, and how best it should be applied. To address this issue we have sequenced 7 genes in the centromeric region of chromosome 15, investigated their SNPs, SNP frequencies, tagSNPs, LD structures, and hap- lotypes in 50 Tibetan subjects, and compared them with those from the Han population. Genetic diversi- ties between the two populations were also quantified. Our results show that the overall genetic variation between the two populations is very little, but there are differences, primarily in allele frequencies, which is a dominating factor for haplotypes and tagSNPs. In general Tibetans have longer LD and less diversity inthe region studied. These data provide genetic evi- dence for the close relationship between the two populations, and support the idea that all populations are fundamentally the same, but also indicate popu- lation variations, particularly in allele frequency, should be taken into account in complex traits/ dis- eases analysis. Data obtained in this investigation not only help us understand the genome region, but also provide road maps for variation study in the genes/ region in Tibetan population.
