Do C H, Cho B W, Lee D H
College of Natural Resource and Life Sciences, Pusan National University, Miryang, Korea .
Asian-Australas J Anim Sci. 2012 Feb;25(2):183-8. doi: 10.5713/ajas.2011.11216. Epub 2012 Feb 1.
To investigate the influence of the prolactin receptor 3 (PRLR3) gene and the retinol-binding protein 4 (RBP4) gene on the production traits of swine, genotyping was performed on 156 and 141 Berkshire pigs, respectively, that were carefully selected for economic traits. The frequencies of allele A in the PRLR3 locus and allele B in the RBP4 locus were 0.50 and 0.42, respectively. Neither locus was in the Hardy-Weinberg equilibrium. After a genotype was assigned to the individuals whose parents had the homozygous genotype, a statistical analysis was conducted for 291 pigs. The animals with the PRLR3 and RBP4 genotypes included 182 and 227 head, respectively. Even though the genotypic effects of PRLR3 (p<0.05) and RBP4 (p<0.01) had a significant influence on the pigs' back fat thickness, the interaction of both genes was not highly significant in terms of the back fat thickness (p = 0.1235). While the estimated epistasis effects of aaBB and aaBb decreased the back fat thickness and reduced the growth rate, the effects of AAbb and aabb increased the growth rate. Despite the insignificant difference in the PRLR genotypes in terms of the days to 90 kg and the average daily gain, the back fat thickness showed a significant difference (p<0.05), and the additive effect of allele A and the dominant effect of the hetero-genotype were -0.377 and 1.206 mm, respectively. The RBP4 genotypes had a very significant effect (p<0.01) on the back fat thickness, the days to 90 kg, and the average daily gain. The additive effects of allele B of the RBP4 locus on the back fat thickness, the days to 90 kg, and the average daily gain were 0.70 mm, -1.3 days and 6.2 g, respectively. Moreover, the dominant effects of the heterozygote for those traits were 0.63 mm, 9.9 days and -45.0 g, respectively. Allele A of the PRLR3 locus favorably influenced the back fat thickness, the days to 90 kg of the body weight, and the average daily gain and its dominant effect unfavorably influenced those traits. Allele B of RBP4 showed an incremental growth rate and back fat thickness, which could lower the lean meat percentage in the carcass. The RBP4 hetero-genotype negatively affected the pork production. These results strongly imply that the selection of allele A of PRLR3 and allele B of RBP4 would produce highly productive pigs in the Berkshire breed. Careful selection of allele B of RBP4 is required because of the increase in the back fat thickness.
为研究催乳素受体3（PRLR3）基因和视黄醇结合蛋白4（RBP4）基因对猪生产性能的影响，分别对156头和141头精心挑选的具有经济性状的伯克夏猪进行了基因分型。PRLR3基因座上等位基因A的频率和RBP4基因座上等位基因B的频率分别为0.50和0.42。两个基因座均未处于哈迪-温伯格平衡状态。在为父母具有纯合基因型的个体确定基因型后，对291头猪进行了统计分析。具有PRLR3和RBP4基因型的动物分别有182头和227头。尽管PRLR3（p<0.05）和RBP4（p<0.01）的基因型效应对猪的背膘厚度有显著影响，但就背膘厚度而言，两个基因的相互作用并不十分显著（p = 0.1235）。虽然aaBB和aaBb的估计上位效应降低了背膘厚度并降低了生长速度，但AAbb和aabb的效应提高了生长速度。尽管PRLR基因型在达到90千克体重的天数和平均日增重方面差异不显著，但背膘厚度显示出显著差异（p<0.05），等位基因A的加性效应和杂合基因型的显性效应分别为-0.377毫米和1.206毫米。RBP4基因型对背膘厚度、达到90千克体重的天数和平均日增重有非常显著的影响（p<0.01）。RBP4基因座上等位基因B对背膘厚度、达到90千克体重的天数和平均日增重的加性效应分别为0.70毫米、-1.3天和6.2克。此外，这些性状杂合子的显性效应分别为0.63毫米、9.9天和-45.0克。PRLR3基因座上的等位基因A对背膘厚度、达到90千克体重的天数和平均日增重有有利影响，其显性效应则对这些性状有不利影响。RBP4的等位基因B显示出生长速度和背膘厚度增加，这可能会降低胴体瘦肉率。RBP4杂合基因型对猪肉生产有负面影响。这些结果强烈表明，选择PRLR3的等位基因A和RBP4的等位基因B将培育出伯克夏品种中高产的猪。由于背膘厚度增加，需要谨慎选择RBP4的等位基因B。
