3种对虾种间RAPD遗传标记

RAPD genetic markers among three species of Penaeid shrimps

用 RAPD技术对对虾属中凡纳对虾、日本对虾和中国对虾基因组 DNA的特异性遗传标记进行分析 ,筛选了 OPK和 OPE两个系列 40个引物 ,有 3 7个引物获得了片段长度在 2 5 0～ 2 2 0 0 bp之间且重复性良好的谱带 ,其中 3 4个引物均可以将 1种、2种甚至 3种对虾分别区别开来。共获得了2 64个扩增片段 ,其中 3种对虾特异性片段 95个 ,每个引物分别获得了 1～ 7个大小不等的片段 ,凡纳对虾获得了 2 8个特异性片段 ,日本对虾获得了 3 2个特异性片段 ,中国对虾获得了 3 5个特异性片段。通过 Popgene1 .3 2种群遗传分析软件包计算结果表明 :日本对虾与中国对虾的遗传距离最大 ,高达 0 .90 96;日本对虾与凡纳对虾的遗传距离次之 ,为 0 .860 8;凡纳对虾与中国对虾的遗传距离最小 ,其值为 0 .62 1 9。根据遗传距离指数 ,用 UPGMA方法进行聚类分析 ,构建系统树。

The index samples of three Penaeid shrimp, P. chinensis, P. japonicus and P. vannamei, were collected from the coastal waters of Korean Peninsula, Taiwan Strait and a hatchery located in Hainan Province respectively. Randomly amplified polymorphic DNA (RAPD) technique was employed in analyzing the specific genetic markers of 8 individuals from each species. The reactions were performed through 94℃ pre denaturing for 5 min, then 45 cycles of 94℃ denaturing for 1 min, 36℃ annealing for 1 min and 72℃ polymerizing for 2 min; The complete extention was conducted at 72℃ for 10 min. 40 primers of OPK and OPE were screened, 37 primers produced reproducible fingerprints with the molecular weight varying from 250 bp to 2 200 bp. The number of RAPD markers amplified by each primer varied from 1 to 7. Those interpretable patterns generated by 34 primers were used as the genetic markers to discriminate the differentiation of the three species. 95 out of 264 amplified fragments were distinctive for the three species, 28 were from P. vannamei, 32 and 35 were from P. japonicus and P. chinensis respectively. Based on the RAPD data, the genetic distances among these three species of Penaeid shrimps were computed by using popgene 1.32 software package. As a result, the biggest genetic distance occured between P. japonicus and P. chinensis with a value of 0.909 6, while smallest genetic distance (0.621 9) came about between P. vannamei and P. chinensis. But the genetic distance between P. japonicus and P. vannamei was 0.860 8. The cluster analysis of the above three species was performed with UPGMA algorithm over their genetic distances. The dendrogram of these three species was constructed.