AIM：To investigate the dynamics of hepatitis Cirus(HCV)variability through putative envelope genes during primary infection and the mechanism of viral genetic evolution in infected hosts.METHODS:Serial serum samples ...AIM：To investigate the dynamics of hepatitis Cirus(HCV)variability through putative envelope genes during primary infection and the mechanism of viral genetic evolution in infected hosts.METHODS:Serial serum samples prospectively collected for12to34months from a cohort of acutely HCV-infected individuals were obtained,and a 1-kb fragment spanning E1and the5′half of e2,including Thirty-three cloned cDNAs representing each specimen were assessed by a method that combined a single-stranded conformational polymorphism(SSCP)and heteroduplex analysis(HDA)method to determine the number of clonotypes hypervariable region,was amplified by reverse transcriptase PCRand cloned.Nonsynonymous mutations per nonsynonymous site(dn),synonymous mutations per synonymous site(ds),dn/ds ratio and genetic distances within each sample were evaluated for intrahost evolutionary analysis.RESULTS:Quasispecies complexity and sequence diversity were lowen in early samples and a further increase after serocon version,although ds value in the envelope genes was higher than dn value during primary infection.The trend,pronounced in most of samples,toward lower ds values in the E1 than in the 5′portion of E2.Quasispecies complexity was higher and E2dn/ds ratio was a trend toward higher value in later asmples during persistent viremia,We also found individual features of HCV genetic evolution in different subjects who were infected with different HCV genotypes.CONCLUSION:Mutations of actively replicating virus arise stochastically with certain functional constaints.Aconplexity quasispecies exerted by a combination of either neutral evolution or selective forces shouws clear differences in individuals,and associated with HCV persistence.展开更多
为了研究来自不同麦区的61份同名小麦地方品种小红芒和6份小红芒麦的遗传演变趋势,对与6个产量相关的农艺性状和高分子量麦谷蛋白亚基（h igh molecu lar we ight gluten in subun its,HMW-GS）组成的变异进行了分析。结果表明,无论是...为了研究来自不同麦区的61份同名小麦地方品种小红芒和6份小红芒麦的遗传演变趋势,对与6个产量相关的农艺性状和高分子量麦谷蛋白亚基（h igh molecu lar we ight gluten in subun its,HMW-GS）组成的变异进行了分析。结果表明,无论是在形态学水平还是蛋白质水平,小红芒和小红芒麦均存在丰富的遗传变异。在形态学水平上,供试材料的变异系数在株高、穗长、有效分蘖数、小穗数、穗粒数和千粒重等农艺性状上的变化范围分别为0.03~0.11、0.06~0.22、0.20~0.65、0.04~0.18、0.14~0.44和0.05~0.29。通过形态学数据计算小红芒和小红芒麦品种内多样性指数和品种间多样性指数,发现前者（0.804）占总多样性指数（0.842）的95.5%,而后者仅占4.5%,可见形态学变异主要来源于品种内而非品种间,说明这些同名材料是由一个品种演变而来。在HMW-GS组成上,共发现了20种亚基组合类型,其中nu ll,7＋8,2＋12和nu ll,7＋8,2＋102种亚基组合出现的频率最高,分别为64.48%和20.00%。比较不同麦区种植的小红芒和小红芒麦的遗传多样性水平,发现无论是在形态学水平还是在蛋白质水平,春麦区材料的遗传多样性均普遍高于冬麦区,并且来自西北春麦区和北部春麦区的材料不仅遗传多样性较高,而且变异来源丰富,其中来自西北春麦区的甘肃天祝一带材料多样性最高,且其所处地理位置便于农作物的传播,故甘肃天祝地区有可能是小红芒的最初种植地点,然后再引种到其他种植区。展开更多
基金the Natural Science Foundation of China,No.3987069
文摘AIM：To investigate the dynamics of hepatitis Cirus(HCV)variability through putative envelope genes during primary infection and the mechanism of viral genetic evolution in infected hosts.METHODS:Serial serum samples prospectively collected for12to34months from a cohort of acutely HCV-infected individuals were obtained,and a 1-kb fragment spanning E1and the5′half of e2,including Thirty-three cloned cDNAs representing each specimen were assessed by a method that combined a single-stranded conformational polymorphism(SSCP)and heteroduplex analysis(HDA)method to determine the number of clonotypes hypervariable region,was amplified by reverse transcriptase PCRand cloned.Nonsynonymous mutations per nonsynonymous site(dn),synonymous mutations per synonymous site(ds),dn/ds ratio and genetic distances within each sample were evaluated for intrahost evolutionary analysis.RESULTS:Quasispecies complexity and sequence diversity were lowen in early samples and a further increase after serocon version,although ds value in the envelope genes was higher than dn value during primary infection.The trend,pronounced in most of samples,toward lower ds values in the E1 than in the 5′portion of E2.Quasispecies complexity was higher and E2dn/ds ratio was a trend toward higher value in later asmples during persistent viremia,We also found individual features of HCV genetic evolution in different subjects who were infected with different HCV genotypes.CONCLUSION:Mutations of actively replicating virus arise stochastically with certain functional constaints.Aconplexity quasispecies exerted by a combination of either neutral evolution or selective forces shouws clear differences in individuals,and associated with HCV persistence.
文摘为了研究来自不同麦区的61份同名小麦地方品种小红芒和6份小红芒麦的遗传演变趋势,对与6个产量相关的农艺性状和高分子量麦谷蛋白亚基（h igh molecu lar we ight gluten in subun its,HMW-GS）组成的变异进行了分析。结果表明,无论是在形态学水平还是蛋白质水平,小红芒和小红芒麦均存在丰富的遗传变异。在形态学水平上,供试材料的变异系数在株高、穗长、有效分蘖数、小穗数、穗粒数和千粒重等农艺性状上的变化范围分别为0.03~0.11、0.06~0.22、0.20~0.65、0.04~0.18、0.14~0.44和0.05~0.29。通过形态学数据计算小红芒和小红芒麦品种内多样性指数和品种间多样性指数,发现前者（0.804）占总多样性指数（0.842）的95.5%,而后者仅占4.5%,可见形态学变异主要来源于品种内而非品种间,说明这些同名材料是由一个品种演变而来。在HMW-GS组成上,共发现了20种亚基组合类型,其中nu ll,7＋8,2＋12和nu ll,7＋8,2＋102种亚基组合出现的频率最高,分别为64.48%和20.00%。比较不同麦区种植的小红芒和小红芒麦的遗传多样性水平,发现无论是在形态学水平还是在蛋白质水平,春麦区材料的遗传多样性均普遍高于冬麦区,并且来自西北春麦区和北部春麦区的材料不仅遗传多样性较高,而且变异来源丰富,其中来自西北春麦区的甘肃天祝一带材料多样性最高,且其所处地理位置便于农作物的传播,故甘肃天祝地区有可能是小红芒的最初种植地点,然后再引种到其他种植区。
