Study On The Genetic Polymorphism Of The Yak GDF-10、IHH And MC4R Gene And Its Association With Growth Trait

The study took molecular biological techniques to research GDF-10gene, IHHgene and MC4R exon regions sequenced of four yak breeds (Gannan yak, Tianzhuyak, Pali yak and Datong yak). Finally, tissue expression were analysis withreal-time PCR of IHH gene, MC4R gene and GDF-10gene in different yak. Theresults were as follows:1. Tissue expression profiling of GDF-10, IHH and MC4R gene in yakThe mRNA expressions profile showed that GDF-10gene, IHH and MC4Rgene were expressed in eight parts of yak in the heart, liver, pancreas, muscle, lung,spleen, kidney and ovary. The GDF-10gene was predominantly expressed in ovaryand spleen in yak. The IHH gene was predominantly expressed in heart, spleen andmuscle in yak. The MC4R gene was predominantly expressed in kidney.2. The genetic polymorphism of GDF-10gene and its association with growth traitsThree SNPs,12116(G/A),12152(C/T) and13041(T/C) were discovered inexon3. The results showed that three locals were at low polymorphic status(PIC<0.25). Analysis of matching chain disequilibrium and haplotype analysis showthat there is a weak chain of balance between the three locals. Analysis of associationof polymorphism with body measurement trait at all mutation loci show that therewere significant effects on body height, body length, weight and herrt girth (P<0.05or P<0.001) and there is no effects on tube girth (P>0.05). Seven haplotypecombinations were found in3different breeding of yak, the ATC and ATT havesignificant effects on body measurement traits and weight.3. The genetic polymorphism of IHH gene and its association with growth traitsTwo SNPs,5855（C/T）and6383(G/A) were discovered in IHH gene. the resultsshowed that tow locals were at high polymorphic status (PIC>0.5). Analysis ofmatching chain disequilibrium and haplotype analysis show that there is a strongchain of balance between the two locals. Analysis of association of polymorphismwith body measurement trait at all mutation loci show that there were significanteffects on body length, weight and herrt girth (P<0.05) and there is no effects on body height and tube girth (P>0.05).4. The genetic polymorphism of MC4R gene and its association with growth traitsOne SNP,437(G/A) was discovered in exon. Through population geneticsanalysis, the results showed that the local was at high polymorphic status (PIC>0.5).The χ2tests showed that the locus was all in the status of Hardy-Weinbergequilibrium (P>0.05). Analysis of association of polymorphism with bodymeasurement trait at all mutation loci show that there were significant effects onbody height, body length, weight and herrt girth (P<0.05) and there is no effects ontube girth (P>0.05).