梅花鹿MSRB3基因多态性及其与茸重性状的关联分析

【目的】 本研究旨在探索梅花鹿甲硫氨酸亚砜还原酶B3（methionine sulfoxide reductase B3，MSRB3）基因多态性及其与茸重性状的关联性。【方法】 选取高、低产茸量的梅花鹿各8只，应用DNA直接测序法检测基因变异位点。采用MassARRAY^® SNP分型技术对314头24月龄梅花鹿MSRB3基因进行基因分型，并结合梅花鹿茸重性状数据进行了关联分析和单倍型分析。【结果】 在梅花鹿MSRB3基因中共发现6个SNPs位点，其中2个SNPs位点位于外显子区域，且突变均未引起氨基酸改变，属于同义突变，其余4个SNPs位点均存在于内含子区域。分型结果显示4个样本未分型成功，其余310个样本进行后续分析。各位点观测杂合度和期望杂合度基本一致，g.44455582 T>C、g.44455759 C>T、g.44414424 T>C、g.44350306 T>C及g.44340836 G>A等5个位点的杂合度较高，均属于中度多态（0.25<PIC<0.5），g.44340734 G>C位点杂合度较低，属于低度多态（PIC<0.25）。卡方检验结果表明，g.44455759 C>T位点偏离Hardy-Weinberg平衡状态（P<0.05），其他5个位点均处于Hardy-Weinberg平衡状态（P>0.05）。对6个SNPs位点的不同基因型与梅花鹿茸重的关联分析结果表明，g.44455582 T>C位点的TT基因型个体茸重极显著高于CC和TC基因型（P<0.01）。单倍型分析结果显示，g.44340734 G>C和g.44350306 T>C、g.44455582 T>C和g.44455759 C>T位点存在强连锁，各产生3种单倍型，在Block 2区块中单倍型TC茸重显著高于单倍型CT （P<0.05）。【结论】 MSRB3基因与梅花鹿茸重性状密切相关，g.44455582 T>C位点和单倍型TC可作为筛选高产梅花鹿的分子标记。

Polymorphism of MSRB3 Gene and Its Association Analysis with Antler Weight Traits in Sika Deer

【Objective】 This study aimed to explore the polymorphism of methionine sulfoxide reductase B3 (MSRB3) gene and its association with antler weight trait.【Method】 8 sika deer with high and 8 sika deer with low antler yield were selected, and the gene mutation sites were detected by direct DNA sequencing. The genetic variation of MSRB3 gene in 314 24-month-old sika deer was genotyped by MassARRAY^® SNP typing technology, and the association analysis and haplotype analysis were carried out combined with the data of antler weight traits of sika deer.【Result】 A total of 6 SNPs were found in MSRB3 gene of sika deer, of which 2 SNPs were located in the exon region, and the mutations did not cause amino acid changes, belonging to synonymous mutations, and the other 4 SNPs were located in the intron region.The typing results showed that 4 samples were not successfully typed, and the remaining 310 samples were subjected to follow-up analysis.The observed heterozygosity of each locus was basically consistent with the expected heterozygosity.The heterozygosity of g.44455582 T>C, g.44455759 C>T, g.44414424 T>C, g.44350306 T>C and g.44340836 G>A were higher, which showed moderately polymorphic (0.25<PIC<0.5).And g.44340734 G>C locus had low heterozygosity, which showed low polymorphism (PIC<0.25).The results of chi-square test showed that g.44455759 C>T deviated from Hardy-Weinberg equilibrium (P<0.05), and the other 5 loci were in Hardy-Weinberg equilibrium (P>0.05).The results of association analysis between the different genotypes of 6 SNPs and antler weight of sika deer showed that the antler weight of TT genotype with g.44455582 T>C locus was extremely significantly higher than that of CC and TC genotypes (P<0.01).The haplotype analysis results showed that g.44340734 G>C and g.44350306 T>C, g.44455582 T>C and g.44455759 C>T were strongly linked, each producing 3 haplotypes.The antler weight of haplotype TC in Block 2 was significantly higher than that of haplotype CT (P<0.05).【Conclusion】 MSRB3 gene was closely related to the antler weight traits of sika deer, g.44455582 T>C locus and haplotype TC could be used as molecular markers for screening high-yield sika deer.