QTL alleles on chromosome 7 from fatty Meishan pigs reduce fat deposition

Abstract

For detecting QTL in the whole swine genome, 1068 pigs from three F2 populations constructed by crossing European Wild boar and Pietrain (W x P), Meishan and Pietrain (M x P), and Wild Boar and Meishan (W x M) were genotyped for genetic markers evenly spaced at approximately 20 cM intervals. AQTL analysis was performed using a least-squares method. Here the results of the QTL analysis on the porcine chromosome 7 are presented. QTL for carcass composition (e.g. head weight, carcass length, backfat depth, abdominal fat and bacon meat) were mapped in the chromosomal region CYPA/CYPD-TNFB-S0102 in M x P and W x M, but not in W x P. The QTL explained 5.3%-27.2% of the F2 phenotypic variance in the two F2 populations. Most traits affected by the mapped QTL were related to carcass fatness. The mode of gene action of QTL was additive. Surprisingly, in contrast to the parental phenotype, the QTL alleles from fatty Meishan were associated with thinner backfat than Pietrain and Wild Boar alleles, suggesting that the genome of the fatty Meishan pig contains genes which can reduce fat content of carcass substantially.

Molecular genetic analysis of the Chinese Erhualian pig breed

“…Several Meishan pigs were exported to the USA and Europe in 1980s, and had been used in breeding programs (Ducos et al, 1992) and in pig genome mapping projects (Geldermann et al, 1996;Rohrer et al, 1996). A study on QTL mapping showed that the Meishan pig possessed QTL alleles which could reduce fat content in carcass, despite its fat appearance (Yue et al, 2003). Research efforts in Europe and the USA have been aimed at explaining the mechanisms underlying the high fecundity and lower embryonic mortality of the Meishan pigs (Rothschild & Ruvinsky, 1998).…”

Polymorphism in exon 2 of pig <I>FIT1</I> gene and its association with fat-deposition-related traits

“…根据Liu [13] 所述方法建立单标记回归统计模型, 采用SAS统计软件(SAS Institute Inc, Version 8.0) glm程序进行单标记方差分析, 同时采用reg程序计 算基因加性效应和显性效应, 并进行显著性检验。 由 于进行多次检验会使总的犯Ⅰ型错误的概率上升, 所 以采用Bonferroni方法对显著性水平进行校正 [14] 。单 标记回归统计所采用模型为: [15] , 它既能被 用作重要的遗传学工具, 也是功能基因组学研究的 对象 [16] 。 [18] 。Yue等 [19] 在"梅 山×皮特兰"和"欧洲野猪×梅山"两个资源家系中, 发 [2] 。过多的脂肪组织将导致肥胖, 由 此会带来诸多并发症。在肥胖病中, 脂肪因子的表 达和由白色脂肪所介导食源性糖类和脂类的处理会 失调, 从而导致高血糖、高血脂、胰岛素耐受和慢 性炎症反应的发生 [2] 。FIT1 基因虽然与脂肪的合成 无关, 但是在脂滴储存方面却发挥了重要的作用 [2] ,…”

Genetic basis of lactation and lactation efficiency in pigs

“…This endoplasmic reticulum protein is also involved in the conversion of cholesterol to bile acids (http://www.ncbi.nlm.nih.gov/gene/51302 assessed October 1, 2014). Earlier studies using microsatellite markers were able map QTL associated with back fat to this region on chromosome 7 (Rothschild et al, 1995;Yue et al, 2003). Results from PigQTLdb showed that QTL for average daily gain (Sanchez et al, 2006) and body weight at slaughter spanned this region (Liu et al, 2008).…”