The Genetic Diversity Analysis Of Three Marine Economy Animals

In the present work, we analyzed the cytochrome oxidase subunit I (COI) in Mactra veneriformis and Pseudosciaena crocea Richardson separately, and analyzed the genetic diversity of Coelomactra antiquata (Spengler) using 16S rRNA sequences and microsatellite DNA. The results will have positive effects on the study of three marine economic animals'phylogenesis, germplasm resources and genetic diversity.The COI gene fragments of Mactra veneriformis sampled from Nantong (NT) and Lianyungang (LYG) Jiangsu province were amplified, sequenced and analyzed. The study revealed that there were 32 haplotypes of 49 samples, and 50 variation sites. As for NT, LYG population, the haplotype diversity was 0.978 and 0.897, respectively. And the average number of nucleotide differences was respective 4.846 and 2.849. This study indicated that the M.veneriformis of NT population was more polymorphic than that of LYG population. The similarities were more than 90% compared with sequences emissed in GenBank(no.AY874531,AB040846). The distance between M.veneriformis and M. chinensis was 0.16. The result of COI sequence was consistent with those of morphological classification.The 16S rRNA sequences were applied to analyze the hereditary feature in Coelomactra antiquata. The partial 16S rRNA sequences of three different regional populations (NT, CL, JM) were amplified, sequenced and analyzed. The results of sequence analysis indicated that the length of the obtained sequence in three regional populations was 446 bp and the content of G+C was 41%. There were 32 variable sites. Analyzed the NJ tree and the variable nucleotide, it concluded that the hereditary feature of CL population was apparently different from the other populations'.In this study, magnetic bead hybridization method was used to enrich the microsatellite loci in Coelomactra antiquate. As a result, 38 microsatellites that repeated no less than five times were found. Among the 38 microsatellites, 68.4% were perfect, 23.7% were imperfect and the rest were compound type (7.9%). Except the biotin-labeled SRS (simple repeat sequence) probe CA and GA, there were ATTG,CGTG and TGTTG in the microsatellites. Microsatellite repeats were mainly range from 5 to 46 times, and the largest repeat number was 70. We designed 14 pairs of SSR-primers using these microsatellite sites. They have positive effects on the study of Coelomactra antiquata genetic diversity.The COI sequence was also used to analyze the hereditary feature of Pseudosciaena crocea Richardson sampled from three different pupulations. After PCR, sequenced and analyzed, the results were as follows: the content of G+C was no more than the content of A+T. There were only 18 variable sites in 625 bp sequence, and the proportion of the haplotype was small. The genetic diversity of Jiangsu wild population was significantly higher than Fujian cultural population, the level of Zhejiang cultural population's genetic diversity was in middle.