Sanchez M-P, Riquet J, Iannuccelli N, Gogué J, Billon Y, Demeure O, Caritez J-C, Burgaud G, Fève K, Bonnet M, Péry C, Lagant H, Le Roy P, Bidanel J-P, Milan D
Station de Génétique Quantitative et Appliquée, INRA, 78352 Jouy-en-Josas Cedex, France.
J Anim Sci. 2006 Mar;84(3):526-37. doi: 10.2527/2006.843526x.
The aim of this work was to estimate whether genetic dissection of QTL on chromosomes 1, 2, 4, and 7, detected in an F2 Meishan x Large White population, can be achieved with a recombinant back-cross progeny test approach. For this purpose, a first generation of backcross (BC1) was produced by using frozen semen of F1 Large White x Meishan boars with Large White females. Four BC1 boars were selected because of their heterozygosity for at least 1 of the 4 regions. The BC1 boars were crossed with Large White sows, and the resulting BC2 offspring were measured for several growth and body composition traits. Contrary to the F2 animals, BC2 animals were also measured for meat quality traits in adductor, gluteus superficialis (GS), longissimus dorsi, and biceps femoris (BF) muscles. Each BC1 boar was tested for a total of 39 traits and for the 4 regions with statistical interval mapping analyses. The QTL effects obtained in BC1 families showed some differences compared with those described in F1 families. However, we confirmed QTL effects for growth in the SW1301-SW2512 markers interval on chromosome 1 and also for body composition in the SW1828-SW2512 markers interval on chromosome 1, in the SW2443-SWR783 markers interval on chromosome 2, and in the SW1369-SW632 markers interval on chromosome 7. In addition, we detected new QTL for growth traits on chromosome 2 and for meat quality traits on chromosomes 1 and 2. Growth of animals from weaning to the end of the test was influenced by the IGF2 gene region on chromosome 2. Concerning meat quality, ultimate pH of adductor, longissimus dorsi, and BF were affected by the interval delimited by UMNP3000 and SW2512 markers on chromosome 1, and a* of GS, L* of BF, and water-holding capacity of GS were affected by QTL located between marker loci SW2443 and SWR783 on chromosome 2. Recombinant progeny testing appeared to be a suitable strategy for the genetic dissection of the QTL investigated.
本研究的目的是评估在一个F2梅山猪×大白猪群体中检测到的位于1号、2号、4号和7号染色体上的数量性状基因座（QTL），能否通过重组回交后代测试方法进行基因剖析。为此，利用F1大白猪×梅山猪公猪的冷冻精液与大白猪母猪杂交，产生了第一代回交（BC1）后代。由于这4个区域中至少有1个区域的杂合性，选择了4头BC1公猪。将BC1公猪与大白猪母猪杂交，并对所得BC2后代的几个生长和身体组成性状进行测量。与F2动物不同，还对BC2动物内收肌、臀浅肌（GS）、背最长肌和股二头肌（BF）的肉质性状进行了测量。对每头BC1公猪总共39个性状以及这4个区域进行了统计区间作图分析。与F1家系中描述的QTL效应相比，BC1家系中获得的QTL效应存在一些差异。然而，我们证实了1号染色体上SW1301 - SW2512标记区间内生长的QTL效应，以及1号染色体上SW1828 - SW2512标记区间内身体组成的QTL效应，2号染色体上SW2443 - SWR783标记区间内身体组成的QTL效应，以及7号染色体上SW1369 - SW632标记区间内身体组成的QTL效应。此外，我们在2号染色体上检测到了新的生长性状QTL，在1号和2号染色体上检测到了肉质性状QTL。从断奶到测试结束动物的生长受2号染色体上IGF2基因区域的影响。关于肉质，内收肌、背最长肌和BF的最终pH值受1号染色体上UMNP3000和SW2512标记界定区间的影响，GS的a值、BF的L值以及GS的持水能力受2号染色体上标记位点SW2443和SWR783之间的QTL影响。重组后代测试似乎是对所研究的QTL进行基因剖析的合适策略。
