Analysis Of Structural Variation(SV) In 10 Genes Of Xiang Pig And Evaluation Of Breeding Value

China is a big pig-raising country.At present,local pig breed resources account for one third of the world’s pig breed resources.At present,the local pig breeds in Guizhou mainly include Xiang pig,Jiangkou carrot pig,Nuogu pig,Kele pig,Rongchang pig,etc.Among them,the Xiang pig has the advantages of strong disease resistance,low cholesterol content,good meat quality,and delicious taste.It is one of the excellent pig breeds in Guizhou.However,the main problems faced by the Guizhou Xiang pig are the slower growth of the individual and the number of litters.Therefore,it hinders the large-scale development of Guizhou Xiang pig breeding industry.In response to the above problems,based on the existing re-sequencing data of the whole genome of the Xiang pig,this study detected ten structural variation（Structural Variation,SV）sites from the Xiang pig genome,all of which are related to the growth and reproduction of the Xiang pig’s QTL.In this study,107 low-yielding Xiang pigs,98 high-yielding Xiang pigs,112 sows,and233 weaned piglets were selected.The weight and body size of 233 weaned piglets were measured every 15 days.The changes were recorded and analyzed.The PCR detection method was used to conduct group research and genotyping of 550 pigs,combined with the collected data of average daily gain every 15 days,body measurements at 150 days of age,Associated analysis with newborn weight,newborn weight,weaning weight,and nipple number is aimed at discovering the polymorphic distribution of structural variation in the genome and its effect on gene expression,in order to find suitable molecular markers for Guizhou Xiang pigs.The selection and breeding of excellent varieties can improve the growth and reproduction performance of Xiang pig.The genotyping results showed that in the structural variants IL1RAPL2-I₁-sv1004,SMAD5-I₄-sv315,MSH4-I₆-sv313,MAPK10-I₈-sv273,the D allele frequency was higher than the I allele frequency.Among variants MEF2C-I₁-sv71,CD53-I₃-sv264,AKT3-I₂-sv282,GSK3B-I₁₁-sv449,IGF2BP3-I₃-sv318,INO80-I₁₄-sv308,the frequency of I allele is higher than that of D allele,The results of polymorphism analysis show that there are polymorphisms and genetic diversity in the ten structural variations.The results of the correlation analysis between genotyping and reproductive traits showed that the structural variation of IGF2BP3-I₃-sv318 showed significant differences between high and low yield pigs（P<0.01）;structural variation MEF2C-I₁-sv71,CD53-I₃-sv264,MAPK10-I₈-sv273,AKT3-I₂-sv282,INO80-I₁₄-sv308 have significant differences between high and low yield pigs（P<0.05）;structural variation IL1RAPL2-I₁-sv1004,SMAD5-I₄-sv315,MSH4-I₆-sv313,GSK3B-I₁₁-sv449 have no significant difference between high-yielding and low-yielding pigs（P>0.05）;in the structural variation MEF2C-I₁-sv71,there was a significant difference between the individual’s birth weight;in the structural variation SMAD5-I₄-sv315,the individual’s birth weight was There is a significant difference between the weight of the weaning litter and the weaning litter;in the structural variation MSH4-I₆-sv313,there is a significant difference between the individual weaning litter weight,and in other structural variations,there is no obvious difference between the three genotypes.The results of the association analysis of genotyping and growth traits showed that 10 structural variants were significantly related to the average daily gain at different developmental stages;IL1RAPL2-I₁-sv1004 was related to body length and body width;SMAD5-I₄-sv315,MSH4-I₆-sv313,MAPK10-I₈-sv273 are significantly related to body height,MEF2C-I₁-sv71 is related to bust circumference;AKT3-I₂-sv282 is related to body length;IGF2BP3-I₃-sv318 and INO80-I14-sv308are related to tube circumference;The three genotypes of CD53-I₃-sv264 and GSK3B-I11-sv449had no significant differences between individuals.Combining the above PCR typing and data analysis results,using the GBLUP breeding model to obtain the average daily gain and litter size traits of individual sports species values,sorting out the breeding results,nine structural variants of IL1RAPL2-I₁-sv1004,CD53-I₃-sv264,SMAD5-I4-sv315,MSH4-I6-sv313,MAPK10-I8-sv273,MEF2C-I1-sv71,AKT3-I2-sv282,IGF2BP3-I3-sv318,and INO80-I14-sv308 were selected for growth.Relevant molecular markers for reproductive traits selection,based on the experimental results,selected Xiang pigs with better comprehensive results,and carried out the next step of cultivation at Dashandi Ecological Breeding Co.,Ltd.of Qingzhen City in the province conducts the next step of cultivation and continues to track its growth status.This article explores whether these ten structural variations affect the growth and reproduction of Xiang pigs.The results obtained are molecular marker-assisted selection for the growth and development of Xiang pigs.In order to provide technical support for the growth and reproduction control of Xiang pig.