论文部分内容阅读
该试验以快长尼罗罗非鱼(Oreochromis niloticus)和普通尼罗罗非鱼2个群体为研究对象,通过PCR扩增与测序,获得GHSR基因5’侧翼区序列77条,片段大小为1 217 bp。共检测出变异位点57个,包括12个插入/缺失位点和45个多态性位点。共发现16种单倍型,其中Hap2可能为原始单倍型。16种单倍型在进化树中聚为A和B 2支,A支中有11种单倍型,在普通群体和快长群体中均有分布,但快长群体中所占比例较高;B支中有5种单倍型,均分布于普通群体中。遗传多样性参数显示普通尼罗罗非鱼群体的核苷酸多样性(Pi)、单倍型多样性(Hd)和平均核苷酸差异数(K)都高于快长尼罗罗非鱼群体。AMOVA分析结果显示快长和普通尼罗罗非鱼2个群体之间的Fst为-0.200 0(P>0.1),表明2个群体间遗传分化不明显,且2个群体的遗传差异主要来自群体内(120%)。
In this study, two populations of Oreochromis niloticus and common Nile tilapia were studied. 77 of 5 ’flanking regions of GHSR gene were obtained by PCR amplification and sequencing. The fragment size was 1 217 bp. A total of 57 mutation sites were detected, including 12 insertion / deletion sites and 45 polymorphic sites. A total of 16 haplotypes were found, of which Hap2 may be the original haplotype. The 16 haplotypes were clustered into A and B branches in the phylogenetic tree. There were 11 haplotypes in A branch, which were distributed in both common and fast growing populations, but were higher in fast growing populations. B branch has five haplotypes, are distributed in the general population. The genetic diversity index showed that the nucleotide diversity (Pi), haplotype diversity (Hd) and mean nucleotide difference (K) of common Nile tilapia population were higher than that of fast nile tilapia group. The results of AMOVA analysis showed that the Fst was -0.200 0 (P> 0.1) between two populations of fast-growing and normal N. niloticus, indicating that the genetic differentiation was not obvious between the two populations, and the genetic differences of the two populations mainly came from the population Inside (120%).