Abstract: The genetic distribution of the polymorphisms of intron 2 of TLR4 gene in four different chicken breeds including Xianju, Baier, Qingyuan, Anka chicken were tested by PCR-SSCP and DNA sequencing in this study. The results indicated that a G1894C mutation existed in four different chicken breeds.There were three genotypes of AA,AB and BB in all the breeds. The results showed that inspected locus was high diversity,the average polymorphism information content (PIC) were Xianju chicken 0.570, Baier chicken 0.597, Qingyuan chicken 0.583, and Anka chicken 0.588, respectively, and were accorded with the law of Hardy-Weinberg equilibrium. The genotypes of G1894C polymorphism locus was no significant differences between the positive and negative groups after chickens infected with Salmonella pullorum (P>0.05).Genotype distribution of G1894C polymorphism locus was highly significant difference between Xianju and Baier chicken (P<0.01), which would provide scientific basis and technological supporting for resistance-related gene analysis in future.

Key words: chicken; TLR4 gene; single nucleotide polymorphisms