Analysis The Genetic Effects Of Krt36 Gene And The Wool-sheep Down Quality Traits Of Altay Sheep

In this study,the quality trait tastes on 512 Altay sheep individuals were conducted,and the effects of age,field and interaction on wool-sheep down traits of Altay sheep were analyzed by using SAS9.1software;and the genetic variation of 4 loci in KRT36 gene at the polymorphism of Altay sheep population were studied;the correlation between this gene and wool-sheep down traits were analyzed by using SAS9.1Chi-square test;in order to lay a basic foundation for the further molecular breeding,the polymorphic loci associated with wool-sheep down traits were screened.For the evaluation and improvement of wool-sheep down quality of Altay sheep,and provide a theoretical basis for the development of sheep down industry,the study on correlation traits of wool-sheep down,and for laying a foundation for breeding high-quality Altay sheep in the future.This study obtained the main results were as follows:1.Age have a very significant effect（P<0.01）on sheep down fiber diameter,diameter standard deviation,Grease content,guard hair whiteness,guard hair lightness,guard hair yellowness traits.There was a very significant positive correlation（P<0.01）between sheep down average diameter of Altay sheep and standard deviation of diameter,Hand length;there was a very significant negative correlation（P<0.01）with Grease content,comfort degree（correlation coefficient up to-0.91）;sheep down fiber Hand length have a very significant positive correlation（P<0.01）with the length standard deviation,the length variation coefficient,sheep down content and sheep down yellowness;have a very significant negative correlation（P<0.01）with Grease content and guard hair content;scoured yield was very significantly positively correlated（P<0.01）with guard hair content,and have a very significant negative correlation（P<0.01）with Grease content and sheep down content;Grease content have a very significant positive correlation（P<0.01）with sheep down content,sheep down whiteness,guard hair whiteness,guard hair lightness and comfort degree;and have a very significant negative correlation（P<0.01）with guard hair content,sheep down yellowness and guard hair yellowness;sheep down content have a very significant negative correlation（P<0.01）with guard hair content,correlation coefficient up to-1.00;sheep down whiteness have a very significant positive correlation（P<0.01）with sheep down lightness（correlation coefficient up to 0.996）,guard hair whiteness and guard hair lightness;and have a very significant negative correlation（P<0.01）with sheep down yellowness and guard hair yellowness;sheep down lightness have a very significantly positively correlated（P<0.01）with guard hair whiteness,and have a very significant negative correlation（P<0.01）with sheep down yellowness,guard hair lightness and guard hair yellowness;sheep down yellowness have a very significantly positively correlated（P<0.01）with guard hair yellowness,and have a very significant negative correlation（P<0.01）with guard hair whiteness and guard hair lightness;guard hair whiteness have a very significantly positively correlated（P<0.01）with guard hair lightness,correlation coefficient up to 1.00;and have a very significant negative correlation（P<0.01）with guard hair yellowness,correlation coefficient up to-0.81;guard hair lightness have a very significant negative correlation（P<0.01）with guard hair yellowness.2.In KRT36-2 locus,three unique SSCP banding patterns were observed named AA,AB,and BB.In the analyzed population,the frequencies of genotypes AA,AB,and BB of KRT36-2 gene were 0.30,0.59,0.11,respectively.Correspondingly,frequencies of allele A and B were 0.60 and 0.40,respectively,in the analyzed population,A allele are a dominant allele.In KRT36-4 locus,the frequencies of genotypes AA,AB,and BB were 0.40,0.28,0.32,respectively;frequencies of allele A and B were 0.543 and 0.458,respectively,A allele are a dominant allele.χ² test showed that KRT36-2 and KRT36-4 gene loci were in good agreement with Hardy-Weinberg equilibrium（P>0.05）.The PIC values of KRT36-2 and KRT36-4gene loci varied from 0.481 to 0.496,and analyzed population possessed moderate genetic diversity.The PCR-SSCP analyze were conducted on the two loci of KRT36-1 and KRT36-3 gene,the results showed that there was only one type of pattern,detected no polymorphism;the different genotype of KRT36-4 gene has no significant effect（P>0.05）on wool-sheep down traits of Altay sheep.In KRT36-2 gene,three genotypes have a very significant effect（P<0.01）on sheep down fiber diameter,comfort degree,scoured yield,sheep down content,guard hair content,hand length,length standard deviation,length variation coefficient and breaking strength;therefore,the KRT36-2 gene locus can be used as the effective DNA marker of marker assisted selection on the sheep down fiber diameter,comfort degree,scoured yield,sheep down content,hand length,length standard deviation,length variation coefficient,and breaking strength.