Comparison of the Internal Transcribed Spacer (ITS) Regions Between Hybrid and Their Parents in Scallop

The remarkable heterosis of the heterozygous F1 derived from Zhikong scallop Chlamys farreri (?) and Japanese scallop Patinopecten yessoensis (?) has been proved during cultured process, and some genetic characteristics analysis have also been conducted using some molecular markers ISSR, SSR, MSAP, and so on. However, no study about the comparison between hybrid offspring and parents based on the nuclear ribosomal DNA internal transcribed spacer (ITS) was explored. In this study, the ITS-1 and ITS-2 of the C. farreri, P. yessoensis and their hybrid were amplified by PCR using specific primers and characteristics of those ITS regions, genetic regularity were analyzed. The results suggested that ITS-2 (334 bp- 352 bp) were a little longer than ITS-1 (241 bp- 256 bp) in length while the average GC content were lower than AT in most individuals, and they all had high genetic variation. Also, the gene flow between the hybrid and female parents were higher than that of hybrid and male parents. Our data implied a commonality that the ITS regions of offspring shared more similarity with that of female parents. This data in the present investigation will help for further studies in heterosis mechanism and utilization of hybrid scallop in China.