Correlation Analysis Of Cashmere Fineness Related InDel Locus Polymorphism In Shaanbei White Cashmere Goats

Shaanbei White Cashmere Goat(SBWC goat)is the dominant agricultural industry in Shan-bei region.In recent years,with the pursuit of economic benefits of meat and cashmere production of goat,farmers are looking for better body size characteristics and cashmere yield of goats.But can not take into account the improvement of wool quality.The application of marker-assisted selection(MAS)is one of the hot molecular biological techniques to improve economic characteristics of cashmere goats quickly and effectively.The KRT26,KRT27,KRT28 genes in keratin gene family,Notch2 and Notch3 genes in Notch pathway,Wnt4,Fzd3,SFRP4 genes in Wnt pathway play a crucial role in the development of cashmere fibers of cashmere goats.It can regulate the cashmere quality or other growth characteristics.Therefore,SBWC goat was selected as the research object in the study to measure the cashmere and growth traits of the goat,collect ear tissues,extract the whole genome DNA of the goat,and detect the Insertion/deletion(InDel)mutation sites of the gene to be tested related to the fineness traits of the goat by using molecular biology and genetic techniques.Correlating and analyzing with the the production and growth traits of cashmere in SBWC goat population,and analyzing the regulation mechanism by using bioinformatics technology.The main results were as follows:1.Polymorphism analysis of the InDel locus in keratin family genesBased on the location information of gene InDel mutation sites provided by Ensembl and NCBI databases,the InDel polymorphism sites of KRT26,KRT27,and KRT28 genes in members of the keratin gene family were analyzed.Finally,it was found that there was polymorphism at the KRT28-P2 locus,but the gene mutation abundance is low(<5%),which prevented subsequent analysis.2.Polymorphisms at the InDel locus of the Notch pathway gene in goats and their association with traits such as cashmere finenessAccording to the location information of gene InDel mutation sites provided by Ensemble and NCBI databases,the InDel polymorphism sites of Notch2 and Notch3 genes,the members of the Notch pathway,were analyzed.Finally,the results showed that there were polymorphisms at the Notch2-P1(rs665021370)and the Notch2-P8(rs653705114)locus,and each locus had three genotypes(II,ID,and DD).The Polymerase information content of the gene was 0.213 and 0.244,which belonged to low degree polymorphism(PIC<0.25).The r2 of linkage imbalance analysis between the two loci was 0.104,indicating that there was no linkage relationship between them(r2<0.33).Based on the above experimental results,chisquare test and correlation analysis were used to determine whether the variation site could affect the cashmere fineness or other growth traits of SBWC goat.For Notch2-P1 locus,it was not correlated to the cashmere fineness of the SBWC goat but was significantly correlated with the body length(P<0.01)(ID genotype was the dominant genotype);There was a significant correlation with body height(P<0.05)(ID and II genotypes were dominant genotypes).For Notch2-P8 locus,it was not correlated to the cashmere fineness of the SBWC goat but was significantly correlated with the wool length(II was the dominant genotype)and chest width(ID genotype was the dominant genotype)(P<0.05);It was significantly correlated with body height traits(P<0.01)(II genotype was the dominant genotype).3.Polymorphisms at the InDel locus of the Wnt pathway gene in goats and their association with traits such as cashmere finenessAccording to the location information of gene InDel mutation sites provided by Ensemble and NCBI databases,the InDel polymorphism site of Wnt4,Fzd3 and SFRP4 genes,the members of Wnt pathway were analyzed.The results showed that there was polymorphism at the Fzd3-P2 locus(rs647744082),which had three genotypes(II,ID,and DD genotypes).The PIC value of the locus is 0.238,belonging to low degree polymorphism(PIC<0.25).Based on the above experimental results,chi-square test and correlation analysis were used to determine whether the variation site could affect the cashmere fineness or other growth traits of SBWC goat.For Fzd3-P2 locus,it was significantly correlated with cashmere fineness of SBWC goat(P<0.05)(ID genotype was the dominant genotype).In conclusion,this experiment analyzed the polymorphism of InDel loci in 8 genes from one gene family and two signal pathways and their association with economic traits such as cashmere fineness.It was found that the Fzd3-P2 locus was significantly correlated with cashmere fineness,indicating that this InDel locus can be used as a molecular marker affecting cashmere fineness in SBWC goats,which is of great significance for the optimization and efficient utilization of cashmere goat germplasm resources in the future.