Variability Of The Nuclear Actin Intron Of Cetaceans And Mitochondrial DNA Of Coilia

Primers for amplifying the cetacean actin intron sequences were come from Baker etc. With these primers, the partial actin intron sequences of finless porpoises (Neophocaena phocaenoides) collected from Chinese waters and other cetaceans were amplified by polymerase chain reaction (PCR). The results suggested a very low level of sequence variation at finless porpoise actin intron sequences; these results also suggested the two subspecies from Yellow sea and the Yangtze River had a relatively closer affinity. The subspecies from South China Sea with the two subspecies had a relatively further affinity. This suggested finless porpoises from Yellow sea and the Yangtze River had a migaration in the history. In combination with some relevant sequences from GenBank, 22 individuals of cetaceans including 17 species of six families were included in the present analysis. The phylogenetic reconstruction supported that species from the same family constituted respective monophyetic groups, and proposed the non-monophyletic origin of river dolphins. The results also suggested beaked whales (Ziphiidae) and bowhead whale (Balaena mysticetus) had a relatively closer affinity.With the universal primers of vertebrate, the partial three mtDNA gene (12S rRNA gene, 16S rRNA gene and Cyt b gene) sequences of Coilia was amplified by using polymerase chain reaction (PCR). In combination with some relevant sequences from GenBank, the sequences variation analysis suggested a very low level at Coilia mtDNA sequences. The analysis supported the view that the differences between Coilia ectenes taihuensis and Coilia ectenes have not risen to subspecies level. The analysis also supported the view that Coilia brachygnathus and Coilia ectenes are the same species. Coilia grayii with the other species of Coilia had a relatively further affinity. Coilia grayii and Coilia ectenes taihuensis had higher genetic diversity.