Study On The Relationship Between Polymorphism Of HSP And NOS3 Gene And Biochemical Index In Serum Of Dairy Cow

Holstein and Holstein×JerseyF₁ dairy cows were used to study heat tolerant traits.The effects and changes of heat stress in the MDA contents,T-SOD,T-AOC and NOS activities were evaluated by colorimetric method in two groups of 40 healthy Holstein and Holstein×JerseyF₁;SNPs of HSP and NOS3 gene were analyzed by PCR-SSCP technique.Gene and genotype frequencies were calculated for the polymorphic loci in HSP gene and NOS3 gene. Variance analysis was completed for distribution of genotypes frequency between different groups.Effects of genotypes in different locus on heat tolerant traits were estimated.The results indicated that:(1)During heat stress period,the MDA contents and T-SOD activities of two groups dairy cows were differ significantly(P＜0.05)and NOS activities had extremely significant differences(P＜0.01),the T-AOC had no significant differences.However,during non-heat stress period,there were no significant differences on the MDA contents,the T-SOD,T-AOC and NOS activities between two groups.The MDA contents decreased(P＜0.01)and the T-SOD,NOS activities increased(P＜0.01)of both Holstein×Jersey F₁ and Holstein;the T-AOC of Holstein serum increased evidently(P＜0.05)between hot and cold season.(2)HSP gene and NOS3 were amplified to identify the nucleotide diversity. Polymorphisms were detected in the loci of HSPA8-intron7,HSPA3-exon1,NOS3-exon3, NOS3-exon4,NOS3-exon8,NOS3-exon13 and NOS3-exon16.The analysis results of polymorphisms were HSPA8-intron7 T deletion mutation and C→G,T→C,HSPA8-exon4 A deletion mutation,HSPA3-exon1 C→A,NOS3-exon8 G→A.(3)The distribution of genotype frequency was differ significantly between Holstein and Holstein×JerseyF₁ in NOS3-exon4(P＜0.05),others had no differences(P＞0.05).(4)Both Holstein and Holstein×JerseyF₁ were midrange polymorphisms on the amplification fragments of HSPA3-exon1 and NOS3-exon13 and both were low polymorphisms on the amplification fragments of HSPA8-intron7;Holstein was high polymorphisms,however,Holstein×JerseyF₁ was midrange polymorphisms on the amplification fragments of NOS3-exon3;Holstein was low polymorphisms and Holstein×JerseyF₁ was midrange polymorphisms on the amplification fragments of NOS3-exon8 and NOS3-exon16.(5)The correlation between NOS3 gene and NOS activity were analyzed by using the data of the two groups respectively.To Holstein,the results showed genotype BC of the HSPA3-exon1 and genotype AB of NOS3-exon13were positively related to NOS activity,the allele B was dominant allele.To Holstein×JerseyF₁,genotype AA and AB of NOS3-exon3 were positively related to NOS activity,the allele A was dominant allele.Genotype CC of NOS3-exon4 was positively related to NOS activity,the allele C of this site was dominant allele.The allele C of this site was dominant allele.(6)In the analysis of the correlation between HSP gene and anti-oxidative capability using data of the two groups of cows respectively.To Holstein,genotype AB and BB of HSPA3-exon1 were positively related to T-SOD activity,the allele B of this site might was dominant allele.To Holstein×JerseyF₁,genotype AA of HSPA3-exon1 was positively related to MDA content,genotype AB and BB was negatively related to MDA content;AB and BB were positively related to T-SOD activity,the allele B of this site might was dominant allele. Genotype AB was positively related to T-SOD activity,the allele B of this site was dominant allele.