基于SSR标记的刺参不同地理群体的遗传结构分析及指纹图谱构建

为分析中、韩、俄沿海刺参(Apostichopus japonicus)种质遗传结构,本研究采用SSR指纹图谱技术对中国青岛、烟台,韩国浦项、群山、木浦,俄罗斯符拉迪沃斯托克的不同刺参群体进行遗传多样性分析和指纹图谱构建。结果显示,13个微卫星座位的平均观测杂合度(Ho)和平均期望杂合度(He)分别为0.47和0.80。13个位点的多态信息含量(PIC)为0.465(AJ06)~0.909(AJ09),除AJ06为中度多态性(0.250.50)。单个位点的等位基因数(A)为10(AJ06)~34(AJ07),平均等位基因数为19.4个。各位点的有效等位基因共83.8个,各位点的有效等位基因数(Ne)为1.7(AJ06)~11.8(AJ09),平均有效等位基因数为6.5。各群体遗传多样性分析结果显示,8个群体的PIC指数为0.6392(韩国木浦)~0.7122(中国青岛),说明相应群体均具有较高的遗传多样性。构建的DNA指纹图谱可将所采集的8个群体区分开。遗传结构分析结果显示,8个刺参群体分配到3个自由交配群中,与UPGMA聚类分析结果相一致。UPGMA聚类分析结果显示,中国青岛、烟台群体与韩国木浦黑参群体聚为一支,俄罗斯刺参群体、韩国浦项黄参群体、韩国群山黑参群体和韩国浦项黑参群体聚为一支,而韩国浦项红参群体作为外群,单独聚为一支。刺参分群及聚类分析表明,不同群体的遗传结构及遗传分化情况不仅与地理位置相关,还与刺参体色有一定的相关性。本研究结果可为刺参种质资源保护及不同地理种群刺参的鉴别提供技术支撑。

Genetic diversity analysis and fingerprint construction for different geographical populations of the sea cucumber (Apostichopus japonicus) based on SSR markers

To evaluate the genetic diversity of the sea cucumber (Apostichopus japonicus) populations, thirteen simple sequence repeat (SSR) loci were used to amplify eight different geographical populations of sea cucumbers collected from China, Korea and Russia. The results showed that the average observed heterozygosity (Ho) and average expected heterozygosity (He) of 13 microsatellite loci were 0.47 and 0.80, respectively. The polymorphism index content (PIC) of the 13 loci ranged from 0.465 (AJ06) to 0.909 (AJ09). Except for AJ06, the loci were moderately polymorphic (0.250.5). The number of alleles (A) ranged from 10 (AJ06) to 34 (AJ07), with an average of 19.4. The total number of effective alleles was 83.8. The number of effective alleles (Ne) ranged from 1.7 (AJ06) to 11.8 (AJ09), and the average number was 6.5. The results of genetic diversity analysis showed that the PIC ranged from 0.6392 (SK-MP-B) to 0.7122 (QD), indicating that all populations had high genetic diversity. The construction of DNA fingerprints could distinguish all eight populations. The eight populations of sea cucumbers were allocated to three free-mating groups using Structure software, which were consistent with those generated using UPGMA cluster analysis. UPGMA cluster analysis showed that the Qingdao, Yantai, and Mokpo black populations were clustered into one group, whereas the Russian, Posco yellow, Kunsan black, and Posco black populations were clustered into another group. The Posco red population was located in the exception group and was located on a separate branch. Cluster analysis showed that the genetic structure and differentiation of the populations of sea cucumbers were not only related to the geographic location but was also related to body color. The results provided the foundation for the genetic identification and genetic resource conservation of the sea cucumber.