Studies On Genetic Polymorphism Of Babylonia Areolata Based On COI Sequence And Microsatellite Markers

Babylonia arealato, commonly named as areola Babylon, is a kind of euryhaline and warm water conch. It is normally restricted to the shallow sea of Fujian, Guangdong and Guangxi in China, the relatively centralized distrib ution. With the development of people’s life, do not only the natural sources but the aqueous environment have faced a challenge. At the same time, this situation will bring a lot of pressure on aquatic organism as well. Babylonia arealato can be regarded as the most popularest creature in 21st century, due to their value. During this period, the requirement of Babylonia arealato appears a linear increasing with a decreasing quantities. Thus, it is vita and imperative to protect this specis and it diversity. SSR and cytochrome oxidase subunit I gene were used to estimate genetic diversity and relationship in DNA of Babylonia arealato which belong to three districts, Dongshan Fujian, Zhanjiang Guangdong, Beihai Guangxi. The results showed that:Nucleotide sequence of 680 bp for COI gene and a high percentage of A+T base composition (about 62.42%)were obtained; singleton poylmorphic sites was 32, nucleotide polymorphisms index (Pi) was 0.00185, the average number of nucleotide differences (K) was 1.252. Taking Babylonia lutosa and Nassarius as outgroups, built the NJ phylogenetic tree, this topology suggested that all the Babylonia areolata clustering together first, then mixed with Babylonia lutosa for one, and finally Nassarius formed independent.14 pairs of primers were picked up from 60 pairs primers and used for PCR and a total of 53 bands were yielded, among which 39 polymorphic(73.58%). Each primer produced 3.786 bands on average and the sizes of the bands were from 220 to 280 bp.The genetic distances between populations varied from 0.0078 to 0.0136. The average genetic distance was 0.011.Results that the genetic diversity mainly presents within the populations not among the populations. It is gene flow that leads to the high genetic identity among the three populations. This also shows that because of the affection of the gene flow, the genetic diversity mainly presents within the populations not among the populations.