Abstract: 【Objective】The aim of this study was to identify the causal mutation determining susceptibility to diarrhoea and oedema disease in piglets of Chinese indigenous pig breeds. 【Method】In the present study, comparative sequencing was used to identify single nucleotide polymorphisms (SNPs) in a positional candidate gene: a1-fucosyltransferase gene (FUT1). The identified SNPs were genotyped by PCR-SSCP in 10 western commercial and Chinese indigenous breeds. The ECF18 adhesion phenotypes were determined in a total of 457 adult pigs from a White Duroc × Erhualian intercross by an in vitro microscopic adhesion assay. The association of the SNP genotypes with in vitro ECF18 adhesion phenotypes was evaluated by SAS software.【Result】Two cSNPs (M229C/T and M714T/C) were identified in the FUT1 gene. M714T/C was a synonymous mutation while M229C/T was a missense mutation leading to a transition of leucine into phenylalanine. Significant difference in allele frequencies of M229C/Twas observed between Chinese indigenous and western commercial pig breeds, but not among Chinese local breeds. The association analysis showed that the M229T/C genotypes had significant association with ECF18 adhesion phenotypes.【Conclusion】The results indicated that M229T/C might be the causal mutation or in linkage disequilibrium with the causative variant determining susceptibility/resistance to ECF18.

Key words: FUT1, M229C/T, ECF18, cSNPs