[Phylogenetic analysis of CO I gene of Oncomelania snails from project of afforestation for schistosomiasis control in marshland endemic regions].
OBJECTIVE
To investigate the genetic difference of cytochrome oxidase I (CO I ) of Oncomelania snails from the project of afforestation for schistosomiasis control in marshland regions, so as to explore the effects of different ecological environments.


METHODS
The snails were collected from 3 different areas, Anqing, Tongling, Wuwei, i.e. the upstream, midstream and downstream regions along the Yangtz River in Anhui Province. Genomic DNA was extracted from the snails, and CO I gene fragments were amplified by PCR, then purified and sequenced. The sequences were edited by using Blast. The CO I genes of O. h. minima and Biomphalaria glabrata were used as the reference of exogenous gene. The genetic distances of the various regions were calculated by the Kimura method and phylogenetic trees were constructed with UPGMA and the NJ method of MEGA (3.1) software.


RESULTS
The amplified CO I gene of the snail was a fragment about 700 bp including 2 primers in length. There were little genetic diversity among the different areas, the identities were higher than or equal to 98%. The genetic distances indicated that the distance between the projects of afforestation and woodland in Anqing was 0.003, while Tongling was 0.019, Wuwei was 0.007. The distances among the three projects of afforestation were 0.003-0.012. The two phylogenetic trees were constructed by the methods of UPGMA and NJ respectively, which took on very similar topo-structure in which isolates of Biomphalaria glabrata located in one clade and all the others in the other one. In the other one clade, O. H. minima located in one clade. There was little genetic diversity among Anqing, Tongling, Wuwei clusters. The afforestations of Anqing and Wuwei clustered into one group, while the woodlands of Anqing and Wuwei appeared as another group.


CONCLUSIONS
There is a little genetic diversity of the snail cytochrome oxidase I (CO I ) in different ecological environments among the upstream, midstream and downstream regions along the Yangtz River in Anhui Province.
Department of Human Parasitology, Wannan Medical College, Wuhu 241002, China.
Yu-Mei
YM
Xu
Shi-Qing
SQ
Zhang
Chuan-Gang
CG
Zhu
D000818:Animals; D003576:Electron Transport Complex IV / Q000235:genetics*; D010802:Phylogeny; D058974:Phylogeography; D012552:Schistosomiasis / Q000517:prevention & control; D012908:Snails / Q000145:classification / Q000235:genetics*; D053833:Wetlands
D003576:Electron Transport Complex IV