We analyzed the two hypervariable segments HVS-I and HVS-II of 108 Chinese Tu ethnic minority group samples for forensic and population genetics purposes, Comparing with Anderson sequence, 79 polymorphic loci in HVS-I...We analyzed the two hypervariable segments HVS-I and HVS-II of 108 Chinese Tu ethnic minority group samples for forensic and population genetics purposes, Comparing with Anderson sequence, 79 polymorphic loci in HVS-I and 40 in HVS-II were found in Chinese Tu ethnic minority group mtDNA sequences, and 90 and 64 haplotypes were then defined. Haplotype diversity and the mean pairwise differences were 0.9903±0.0013 and 5.7785 in HVS-I, and 0.9777±0.0013 and 3.5819 in HVS-II, respectively. By analyzing the hypervariable domain from nucleotide 1,6180 to 1,6193 in HVS-I, we defined some new types of sequence variations. We also compared the relationship between Tu population and other populations using mtDNA HVS-I sequences. According to Rst genetic distances, the phylogenetic tree showed that the Tu population, the Xi＇an Han population, the Chinese Korean, and the Mongol ethnic group were in a clade. This indicated a close genetic relationship between them. There were far relations between the Tu population and other Chinese southern Han populations, Siberian, European, African, and other foreign populations. The results suggest that Tu population has a multi-origin and has also merged with other local populations.展开更多
Chinese culture has been disrupted and distorted for several times during its history. Two cases are introduced to discuss how the Chinese culture was affected by the various factors. Some cultural legacies of China m...Chinese culture has been disrupted and distorted for several times during its history. Two cases are introduced to discuss how the Chinese culture was affected by the various factors. Some cultural legacies of China may be lost, and the way for remedy is to keep Chinese culture open up and in a competitive environment.展开更多
The ataxin-2 （ATXN2） gene is located on human chromo-some 12q24.1. In normal individuals, the coding region in exon 1 of this gene has fewer than 31 CAG repeats （Yu et al., 2005： Laffita-Mesa et al., 2012）. Howev...The ataxin-2 （ATXN2） gene is located on human chromo-some 12q24.1. In normal individuals, the coding region in exon 1 of this gene has fewer than 31 CAG repeats （Yu et al., 2005： Laffita-Mesa et al., 2012）. However, an abnormal expansion of CAG trinucleotide repeats results in the aggre-gation of polyglutamine （polyQ）, which causes spinocer-ebellar ataxia type 2 （SCA2） （Pulst et al., 1996）. The expanded alleles have more than 32 repeats in the affected individuals, and generally there is an inverse correlation between CAG repeat length and age of onset （Pulst et al., 1996）. SCA2 is an autosomal dominant inheritance neurodegenerative disease, whose major clinical feature is progressive cerebellar ataxia. Atrophies of the brainstem and frontal lobe have been frequently detected by magnetic resonance imaging （MRI） （Yamamoto-Watanabe et al., 2010）. This disease has the strong effect on sensory and motor control.展开更多
文摘We analyzed the two hypervariable segments HVS-I and HVS-II of 108 Chinese Tu ethnic minority group samples for forensic and population genetics purposes, Comparing with Anderson sequence, 79 polymorphic loci in HVS-I and 40 in HVS-II were found in Chinese Tu ethnic minority group mtDNA sequences, and 90 and 64 haplotypes were then defined. Haplotype diversity and the mean pairwise differences were 0.9903±0.0013 and 5.7785 in HVS-I, and 0.9777±0.0013 and 3.5819 in HVS-II, respectively. By analyzing the hypervariable domain from nucleotide 1,6180 to 1,6193 in HVS-I, we defined some new types of sequence variations. We also compared the relationship between Tu population and other populations using mtDNA HVS-I sequences. According to Rst genetic distances, the phylogenetic tree showed that the Tu population, the Xi＇an Han population, the Chinese Korean, and the Mongol ethnic group were in a clade. This indicated a close genetic relationship between them. There were far relations between the Tu population and other Chinese southern Han populations, Siberian, European, African, and other foreign populations. The results suggest that Tu population has a multi-origin and has also merged with other local populations.
文摘Chinese culture has been disrupted and distorted for several times during its history. Two cases are introduced to discuss how the Chinese culture was affected by the various factors. Some cultural legacies of China may be lost, and the way for remedy is to keep Chinese culture open up and in a competitive environment.
基金supported by the National Natural Science Foundation of China(No.30400264)the Natural Science Foundation of Yunnan Province,China(No.2008ZC068M)the Chinese National High Technology Research and Development Program(No.2012AA021802)
文摘The ataxin-2 （ATXN2） gene is located on human chromo-some 12q24.1. In normal individuals, the coding region in exon 1 of this gene has fewer than 31 CAG repeats （Yu et al., 2005： Laffita-Mesa et al., 2012）. However, an abnormal expansion of CAG trinucleotide repeats results in the aggre-gation of polyglutamine （polyQ）, which causes spinocer-ebellar ataxia type 2 （SCA2） （Pulst et al., 1996）. The expanded alleles have more than 32 repeats in the affected individuals, and generally there is an inverse correlation between CAG repeat length and age of onset （Pulst et al., 1996）. SCA2 is an autosomal dominant inheritance neurodegenerative disease, whose major clinical feature is progressive cerebellar ataxia. Atrophies of the brainstem and frontal lobe have been frequently detected by magnetic resonance imaging （MRI） （Yamamoto-Watanabe et al., 2010）. This disease has the strong effect on sensory and motor control.
