四川光壳钉螺微卫星遗传变异的小尺度空间自相关分析

目的 采用小尺度空间自相关分析方法对四川省普格县的湖北钉螺自然居群微卫星(SSR)遗传变异的空间结构进行分析,探讨湖北钉螺自然居群遗传变异的空间分布特征.方法 选用5对SSR引物对湖北钉螺基因组DNA进行扩增,选择频率在15%～85%的72个SSR等位基因,运用等样本对频率方法划分14个距离等级分别计算空间自相关系数Moran's I,.结果 5对SSR引物经PCR扩增共得到274个等位基因,SSR等位基因的平均多态信息量高达0.965,表现出很高的遗传多态性.钉螺种群中39个SSR等位基因的遗传变异存在一定程度的空间结构,表现为不同模式的正空间自相关.根据这39个等位基因在14个距离等级上的平均Moran's I值,可以发现随着距离增大正空间自相关性逐渐减小,但未发现表现为负空间自相关的距离等级和等位基因.结论 普格县湖北钉螺种群中SSR遗传变异的空间分布,表现为随着距离增加而减少的正空间自相关性.

Simple sequence repeat variation and small-scale spatial autocorrelatian analysis on smooth-shell populations of Oncomelania hupensis in Sichuan province

Objective To analysis the spatial autocorrelation on the small-scale distribution of the genetic variation in the population of Oncomelania hupensis in Puge county, Sichuan province, using simple sequence repeat (SSR) marker. Methods 5 pairs of SSR primer were used to amplify the genomic DNA of Oncomelania hupensis, and the alleles with frequency ranging from 15% to 85% were used to calculate Moran' s I spatial autocorrelation coefficients in 14 distance band based on equal numbers of paired samples. Results A total of 274 alleles were scored by 5 pairs of SSR primer, the average polymorphic information content of the 274 alleles were 0.965 which indicated a high level of genetic diversity. 39 alleles showed different patterns of positive spatial autocorrelation of genetic variation, which was non-random spatial structure. When the distance band increased, the spatial auto-correlativity decreased based on the average Moran' s I value at 14 distance band. The alleles which showed a negative spatial autocorrelation were not found in any distance band. Conclusion The spatial distribution of the genetic variation of SSR showed positive spatial autocorrelation in the population of Oncomelania hupensis, and the spatial auto-correlativity decreased with the increase of distance band.