Analysis Of The Relationship Between Polymorphism Of Leptin And Seasonal Estrous In Sheep

104nonseasonal estrus Hu sheep and90seasonal estrus Altay sheep were selected to conductthis experiment.By combining PCR-SSCP assay,we detected Leptin Gene polymorphisms of thesetwo breeds sheep.By studying the relationship of the selected polymorphisms of leptin gene andseasonal estrus sheep, we got the following result:The genotype BB was dominant in Altay,however the genotype AA was dominant in Husheep,by detecting three genotypes AA, AB and BB on the amplified fragment of the exon2. Thegenotype distributions were significantly different (P<0.001) between two groups, especiallydemonstrated that genotype BB was benefit for seasonal estrus. Meanwhile, this genotype locatesin the middle of the Hardy-Weinberg. The genotype CC was dominant in Hu sheep.However,genotype DD isn’t detected in Hu sheep, by detecting three genotypes CC, CD and DD on theamplified fragment of the exon3. The genotype distributions were significantly different (P<0.01)between two groups, which demonstrates this genotype locates in the middle of theHardy-Weinberg.Using gene sequencing assay, compared with Hu sheep, we found that three consecutivebases TTG inserted and C/T mutated in intron1and G/T mutated in exon3of leptin, and codingamino acid turns valine into leucine.By analyzing the related indexes on polymorphisms of leptin gene and seasonal estrussheep,we found that there is a significant association between difference on Leptin genesequencing and seasonal estrus sheep, which may be one reason why sheep will need PCR-SSCP.Meanwhile, the reason also can be one reference to help us select the nonseasonal estrus sheep.