Study On Polymorphism Of AR Gene And Its Relationship To Antler Productivity In Sika Deer

Androgen receptor (AR) gene is located on human’s chromosome Xq11-12, containing eight exons and seven introns. AR is a member of the steroid hormone receptor gene family. The studies of AR are mainly focused on human beings but nothing is known about the AR in deer. The yield of antler is a foundational measurement standard during breeding work of deer and the production impacts the productive efficiency directly. Antler productivity is a sex-limited character and it displays late in the life cycle. The cycle of traditional selection is long and the effect is slow. Marker-assisted selection method can implement early selection, which would illuminate molecular regulatory mechanism of antler productivity. And it has important theoretical and practical significance to improve selection efficiency and save the cost of breeding.The present study took three sika deer (ShuangYang sika deer, DongFeng sika deer and LongTanShan sika deer) as objects to study single nucleotide polymorphisms (SNPs) within AR gene and analyze its relationship with the yield of antler of this three sika deer. It will provide scientific basis and technical support to molecular breeding of antler production of sika deer.Based on the AR gene sequences of Bos taurus in GenBank(NC007331, Z75313, Z75314, Z75315), nine primer pairs for AR gene were designed. Polymorphism of AR gene in three sika deer populations were detected by PCR-SSCP and sequencing. Mutable sites were detected in exon3 and exon8 of AR gene. And the associativity of the gene polymorphism with the antler productivity of sika deer were also explored. The results were as follows:1.The amplification products of two pairs primers in nine existed polymorphism. And the polymorphic sites were in exon3 and exon8 of AR gene.2. There are 4 bases mutation in the exon3 of AR gene, comparing the AR gene sequence of ShuangYang sika deer, DongFeng sika deer, LongTanShan sika deer with Bos taurus. The homology was 97%.3. Three genotypes (AA, AB and BB) were detected in ShuangYang and DongFeng sika deer, but only two genotypes (AA and BB) were detected in LongTanShan sika deer. Comparing AA genotype with BB genotype, there was mutation(T→C)at 75 bp, which gave rise to amino acid change(Val→Ala). x2 fitness test showed that the distribution of different genotypes with primer exon3 of AR gene in ShuangYang sika deer was in Hardy-Weinberg equilibrium, but that were Hardy-Weinberg disequilibrium in DongFeng and LongTanShan sika deer.4. In the ShuangYang and DongFeng sika deer population, association analysis showed that the difference of antler production between genotype AB and genotype AA was significant(P＜0.05), the difference between genotype BB and genotype AB was not significant(P>0.05), the difference between genotype BB and genotype AA was not significant yet(P>0.05).5. There are 4 bases mutation in the exon8 of AR gene, comparing the AR gene sequence of ShuangYang sika deer with Bos taurus. The homology was 97%.6. Population genetic analysis suggested that, two genotypes (CC and DD) were detected in the exon8 of AR gene in ShuangYang sika deer, x2 fitness test showed that the distribution of different genotypes with primer exon8 of AR gene in ShuangYang sika deer was Hardy-Weinberg disequilibrium.