Departamento de Zootecnia, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista, Via de Acesso Prof. Paulo Donato Castellane, Jaboticabal, SP 14884-900, Brazil.
Mol Biol Rep. 2012 Feb;39(2):1541-9. doi: 10.1007/s11033-011-0893-0. Epub 2011 Jun 3.
The objective of this study was to describe the VNTR polymorphism of the mucin 1 gene (MUC1) in three Nelore lines selected for yearling weight to determine whether allele and genotype frequencies of this polymorphism were affected by selection for growth. In addition, the effects of the polymorphism on growth and carcass traits were evaluated. Birth, weaning and yearling weights, rump height, Longissimus muscle area, backfat thickness, and rump fat thickness, were analyzed. A total of 295 Nelore heifers from the Beef Cattle Research Center, Instituto de Zootecnia de Sertãozinho, were used, including 41 of the control line, 102 of the selection line and 152 of the traditional. The selection and traditional lines comprise animals selected for higher yearling weight, whereas control line animals are selected for yearling weight close to the average. Five alleles were identified, with allele 1 being the most frequent in the three lines, especially in the lines selected for higher means for yearling weight. Heterozygosity was significantly higher in the control line. Association analyses showed significant effects of allele 1 on birth weight and weaning weight while the allele 3 exert significant effects on yearling weight and back fat thickness. Despite these findings, application of this marker to marker-assisted selection requires more consistent results based on the genotyping of a larger number of animals in order to increase the accuracy of the statistical analyses.
本研究的目的是描述三个用于选择育肥牛的 Nelore 品系中粘蛋白 1 基因（MUC1）的 VNTR 多态性，以确定该多态性的等位基因和基因型频率是否受到生长选择的影响。此外，还评估了该多态性对生长和胴体性状的影响。分析了出生、断奶和育肥体重、臀部高度、背最长肌面积、背膘厚度和臀部脂肪厚度。共使用了来自塞特拉辛霍家畜研究中心、祖特卡西亚的 295 头 Nelore 小母牛，包括 41 头对照品系、102 头选择品系和 152 头传统品系。选择和传统品系包含了选择育肥体重较高的动物，而对照品系的动物则选择育肥体重接近平均水平的动物。鉴定出 5 个等位基因，其中等位基因 1 在三个品系中最常见，特别是在选择育肥体重较高的品系中。在对照系中杂合度显著较高。关联分析表明，等位基因 1 对出生体重和断奶体重有显著影响，而等位基因 3 对育肥体重和背膘厚度有显著影响。尽管有这些发现，但该标记的应用需要在更大数量的动物中进行基因分型，以提高统计分析的准确性，从而获得更一致的结果，才能应用于标记辅助选择。
