Studies On The Inheritance Of Hair Color And The Relationsip With Other Pig Breeds Of Pudong White Pig

Pudong White pig has the characteristics of prolificacy, high quality of meat and strong adaptability. It's the only one of Chinese indigenous pig breeds which has full white hair color, and has been listed as one of the key conserved breeds of the national Ministry of Agriculture. However, the molecular genetic basis of the white color of Pudong White pig is unknown till now, as well as the evolutionary relationship with the other pig breeds. These unclear issues seriously affect the conservation, breeding and utilization of the species. In view of this, our study focused on the following two points and made a series of important results:(1) Aanalysis of KIT gene of Pudong White pig. We used the PCR-SSCP and DNA sequencing techniques to detect the KIT gene which was already proved to be an important gene in controlling the hair color of Landrace and Large White. The results demonstrate that Pudong White also has the G→A mutation in intron17 and the AGTT deletion in intron18 of KIT gene which are totally same with the mutations in Landrace and Large White, but different from Rongchang pig. Our results illustrate that, being an indigenous pig breed, the white color of Pudong White pig has special value, but we could not identify its genesis just from the hair color.(2) Analysis of mtDNA D-loop of Pudong White pig. To resolve the issues continually, we sequenced 25 Pudong White pigs' mitochondrial DNA (mtDNA) D-loop regions of ~1200bp, and compared the mtDNA of Pudong White pig with other domestic and foreign pig breeds' D-loop regions available on GenBank. The further phylogenetic analyses were also conducted between the species. The results showed that 25 Pudong White pigs compose a unique subgroup (the bootstrap value is 97%) and the average genetic distance is 0.0002±0.0001 within the group that is far less than from other breeds (especially to foreign breeds). This demonstrated that Pudong White pig is an independent indigenous breed on the maternal origin.Obviously, this study is great helpful to identify the phylogenetic origin. Moreover, it is significantly meaningful for the conservation, breeding and utilization of Pudong White pig. With the constant development of the molecular technology and various related researches, new insight and perspective in the more in-depth study on Pudong White pig would be developed.