Genetic Effect Study Of KRT85,Notch2 And ADAM9 Genes On Wool Traits Of Chinese Merino (Xinjiang Type) Sheep

Using the Chinese Merino sheep as our study material, in this study we filtered out the SNPs of candidate genes KRT85, Notch2 and ADAM9, classify the SNPs of candidate genes adopting the PCR-SSCP technique, and analyse the relationship between wool traits and SNPs using the SAS9.1 least Squares method.The main purpose of this study was intended to obtain the corresponding molecular genetic informat ion, to gain DNA markers which is associated with wool traits, and also to lay the foundation for protection of genet ic resources, development and utilization of Chinese Merino (Xinjiang type) sheep, improve and enhance th e production performance of sheep in order to provide a theoretical basis for molecular breeding of fine-wool sheep.The main results of this study are following:1. Testing the SNPs which related to the wool traits using the DNA pool Filtering the SNPs which related to the wool traits in very thick and thin DNA pools using the resequencing t echnology:A total of five significant SNPs markers are filtered out, respectively two SNPs for KRT85, two SNPs for Notch2 and one SNP for ADAM9 gene.2. Polymorphism detection of KRT85, Notch2 and ADAM9 genes PCR-SSCP methods showed that three unique SSCP genotypes were observed named as AA、AB and BB, respectively, in KRT85-1 and ADAM9 loci, and two genotypes were observed named as AA and AB, respect-ively, in KRT85-2, Notch2-1 and Notch2-2 loci. The five locus were in the Hardy-Weinberg disequili brium (P>0.01). KRT85-1 locus possessed low genetic diversity, and KRT85-2、Notch2-1、Notch2-2、ADA M9 loci possessed moderate genetic diversity. Direct sequencing results showed that KRT85-1 locus detected two mutations 133bpA/C,46bp-/A; KRT85-2 locus detected five mutations 89bpG/A,188 bpG/A,196bp A/T,190bpA/C,137bpG/; Notch2-2 locus detected five mutations 54bpC/T,162bpG/A,166bp C/A,167bp A/ T,55bpA/-; ADAM9-1 locus detected two mutations 78bpG/C,35bpA/-.3. Association analysis between KRT85、 Notch2 and ADAM9 genes and wool traits of Chinese Merino (Xinjiang type) sheep.The association between KRT85、Notch2 and ADAM9 genes and wool traits was anal-yzed by adopting SAS 9.1; the results showed that different genotypes of KRT85-1 gene had significant difference(P<0.05) on bending number of Chinese Merino (Xinjiang type) sheep; KRT85-2 gene has signifi cant difference(P<0.05) on body size, physical appearance rating, live weight after shearing, live weight afte-r shearing after correct and grade; Notch2-1 gene has little highly significant difference(P<0.07) on live weight after shearing, wool length, body size; Notch2-2gene has highly significant difference(P<0.07) on bending number; different genotypes of ADAM9 gene had significant difference(P<0.05) on greasy weight.