Analysis Of FcRn As A Candidate Gene Of IgG Concentration In Sow Colostrum

Colostrum characters have been done little research due to the complexity of the colostrum characters and it's improvement is little in the breeding. Because of the relationship of IgG concentration in colostrum of the sow and IgG concentration in the piglet serum , molecule breeding to IgG concentration in colostrum of the mother turn to be a optimistic field.The content of this research was screening polymorphism of FcRn (neonatal Fc receptor) of the swine and analyzing whether it could be a candidate gene or molecular marker to improve IgG concentration in colostrum of the mother.PCR-SSCP analysis was used to detect SNP in FcRn of the swine in a 207 sow population which were reared in the same condition involving 3 breeds-Duroc(D), Landrace (LX Large-Yorkshire(Y).5 pairs of primers were designed in order to get the sequence of FcRn by BAC and PCR-sequencing, and 7 pairs of primers were designed in order to get DNA fragments by PCR. The results of SSCP analysis on those DNA fragments told us that the polymorphisms exit in exon 3 , introns 5, exon 6 in this population. By cloning and sequencing those DNA fragments with polymorphisms we found 3 SNPs, they were as following: T→C in exon 3, G→C in introns 5,A→C in exon 6, in which A→C in exon 6 was non-synonymous substitution, it resulting in Thr→Arg.Association analysis of IgG concentration in colostrum of the swine , piglet litter averge increased weight of 3 days and FcRn gene polymorphisms was done by SAS software and the results showed that breed and averge weight of firstborn piglet in a litter change site in exon6 had significant effect on piglet litter averge increase weight of 3 days ( P<0.05); breed and parturition number of the sow, change sites in introns 5 and in exon6 had significant effect on IgG concentration in colostrum of the mother (P<0.05).Mutiple T comparisons in change sites that had significant effect on product character indicated that IgG concentration in colostrum of the mother between genotype CC and genotype CD> DD were significant(p<0.05); IgG concentration in colostrum of the mother and piglet litter averge increase weight of 3 days between genotype EE, EF > FF in exon 6 were significant(p<0.05), the IgG concentration in colostrum of the mother between genotype FF and EE > EF were very significant (P<0.01) and the IgG concentration in colostrum of the mother of genotype EF was much higher than EE,but piglet litter averge increase weight of 3 days of genotype EF was much lower than EE.The result of the research showrthe change sites in introns 5 and exon 6 had significance effect on IgG concentration in colostrum of the mother(p<0.05).The change site in exon 6 had significance effect on IgG concentration in colostrum of the mother and piglet litter averge increase weight of 3 days (p<0.05); the change site in introns 5 had significance effect on IgG concentration in colostrum of the mother and did not have significance effect on piglet litter averge increase weight of 3 days (p>0.05).