| Prion protein gene(PRNP)is an important gene regulating prion protein expression,which has high variability.It was found that there are 10 amino acid variation sites(102,127,143,146,154,211,218,219,222 and 240)and three synonymous substitution sites(42,125 and 138)in PRNP gene coding region of goat.PRNP gene is located on goat chromosome 13,It was found that PRNP gene genetic diversity was significantly related to the resistance / susceptibility of urticaria.The blood samples of 851 goats were collected from a large-scale goat farm in Shandong Province,including 464 Lubo goats,131 Laiwu black goats and 256 Laoshan dairy goats.The goats were divided into three groups according to their ages,under 1 year old group,1-2 year old group and over 2 year old group.The technical route adopted is:Firstly,60 Lubo goats were selected to extract DNA,design primers and mix pool sequencing to find out the possible polymorphic sites of the gene;The DNA samples of each goat were sequenced,and the genotypes of each polymorphic site were determined by chromas 2according to the peak map;Popgen 32 and SPSS 22 were used to analyze the effect of PRNP gene polymorphisms and varieties on blood traits,and to find out the dominant genotypes related to blood traits.The test results are as follows:1、Eleven SNP polymorphisms were found in the study population,among which three SNP loci(NH1,NH2 and 3’UTR)were found for the first time.Two polymorphic sites and mutation base information were found in intron region,NH1(G → A)and NH2(C → G),respectively;8 polymorphic loci in CDS region are CDS42(G→A)、CDS102(T→G)、CDS138(T→C)、CDS143(A→G)、CDS146(A→G)、CDS211(G→A)、CDS222(C→A)、CDS240(A→C);One SNP found in 3’UTR area was named 3’UTR(C→G)。The heterozygosity,F-statistics and gene flow of all loci of the three goat breeds were also estimated.2、Combined with the references,it can be determined that there are four polymorphic loci related to the resistance of goat to itch,include CDS222R、CDS211O、CDS146N and CDS143 L,The favorable alleles were all mutants.Comprehensive analysis showed that the advantageous or dominant polymorphic loci of Lubo goat,Laiwu Black Goat and Laoshan milk goat were different,They are CDS146 、 CDS143 and CDS211,The frequencies of favorable alleles and homozygous genotypes were 0.2764 and 0.0793、0.5846 and 0.3231、0.1445 and 0.1445。On the other hand,The number of individuals in the three breeds was small in locu CDS222,which indicated that this locus was not the dominant locus in Shandong goat population.3、The breed and age of goat had significant or extremely significant influence on most blood characters(P < 0.05 or P < 0.01).Among them,goat breeds had significant effects on lymphocyte ratio,intermediate cell ratio and granulocyte ratio(P < 0.01),There were significant effects on the total number of red blood cells,hemoglobin concentration and red blood cell distribution width(SD)(P < 0.05).Goat’s age had significant effects on lymphocyte,hematocrit,mean corpuscular volume,hemoglobin concentration,red blood cell distribution width(SD and CV)(P < 0.01),and on leukocyte count,lymphocyte ratio,intermediate cell ratio,intermediate cell and granulocyte(P < 0.05).4、Among the 11 loci,NH1,CDS138,CDS143,CDS211 and CDS222 had no significant effect on blood traits(P < 0.05),NH2,CDS42,CDS102,CDS146,CDS240 and3’UTR had significant effect on at least one blood trait(P < 0.05 or P < 0.01).Among them,NH2 had significant effect on lymphocyte ratio,intermediate cell ratio and granulocyte ratio(P < 0.05),The dominant genotypes were DD,CC and CC,respectively;CDS42 had significant effect on granulocyte ratio(P < 0.05),The dominant genotype was FF;CDS102had a significant effect on granulocyte ratio(P < 0.01),The dominant genotype was HH;There was significant effect on granulocytes(P < 0.05),The dominant genotype was GG;CDS146had significant effect on lymphocyte ratio(P < 0.05),The dominant genotype was MM;CDS240 had significant effect on lymphocyte ratio and intermediate cell ratio(P <0.05),The dominant genotype was SS and TT;Site 3’UTR had significant effect on the intercellular ratio(P < 0.05),The dominant genotype was VV.5、The analysis of interaction effect showed that there were interaction betweenvarieties and ages in more than ten indexes except the total number of leukocytes,hemoglobin and hemoglobin content(P < 0.05 or P < 0.01).There were significant interaction characters between varieties and loci NH2,CDS102,CDS143,CDS211,CDS240 and 3’UTR(P < 0.05 or P < 0.01).in summary,PRNP gene is abundant in Shandong goats,and there are specific loci;The favorable or dominant polymorphic loci of anti pruritus in Lubo,Laiwu black and Laoshan dairy goats are different,which are CDS146,CDS143 and CDS211 respectively;Six loci,NH2,CDS42,CDS102,CDS146,CDS240 and 3’UTR,had no significant effect on at least one blood trait;Most of the blood traits have interaction between varieties and age,and some of them have interaction between varieties and polymorphic loci. |
