By using PCR-based molecular method,four new pear SFBB-γ genes were isolated from 8 pear cultivars known as S-genotypes.Length of PCR products from eight pear cultivars was around 1 200 bp.Sequencing the specific PCR fragments revealed four new SFBB-γ genes that were respectively named as SFBB 16-γ (EU422956),SFBB 17-γ (EU422957),SFBB 28-γ (EU422960)and SFBB 35-γ (EU422958).As for different SFBB-γ genes,variation in amino acid was higher in F-box region and variable region 1,and lower in variable region 2 to 4.Phylogenetic analysis showed that there was a high level of difference between Japanese pear(Pyrus pyrifolia) SFBB-γ genes and Xinjiang pear(P.sinkiangensis) SFBB-γ genes,as well as Japanese pear SFBB-γ genes and Chinese white pear(P.bretschneideri) SFBB-γ genes.The results might reflect their genetic relationships among the species.
