Sequence Comparison of Mitochondrial 16s rRNA Gene Segment in Penaeids

A partial fragment of 16s rRNA mitochondrial gene was amplified by PCR from Penaeus monodon samples collected from the west and east coast regions of India. The amplified 520 bp of 16s rRNA mitochondrial gene segment of P. monodon from different locations on sequencing revealed similar sequence identity and no apparent sequence variation could be observed in this amplified segment. Amplification of 16s rRNA mitochondrial gene segment was also carried out from Marsupenaeus japonicus and Fenneropenaeus indicus. The sequence identity of 16s rRNA mitochondrial gene segments between P. monodon and M. japonicus, between P. monodon and F. indicus and between M. japonicus and F. indicus was found to be 91%, 92% and 91% respectively. The high level of sequence identity observed in the amplified PCR products of 16s rRNA mitochondrial gene segment of P. monodon isolated from the east and west coast regions of India, suggests that it will be more useful to focus on other variable mitochondrial DNA regions which may be more informative for population studies.