猪肉嫩度相关QTL整合定位与基因关联分析研究

为了优化猪肉嫩度相关数量性状位点(quantitative trait loci，QTL)，为基因的精细定位和克隆奠定基础。通过Meta分析，利用数学模型整合猪肉嫩度相关QTL，分析已知候选基因与“真实”QTL的关联性。收集猪肉嫩度相关QTL，将其逐一映射到美国肉畜研究中心(USDA-MARC 2.0)公布的猪遗传连锁图谱，构建整合图谱。进行Meta分析，得到精确性更高的“真实”QTL，并将已知候选基因映射到整合图谱，比较候选基因与各“真实”QTL的关联性。研究表明：99个猪肉嫩度相关QTL映射到参考图谱，构建成新的整合图谱。通过Meta分析，定位了16个“真实”QTL，图距2.42~25.18 cM，比较原始QTL缩短29.21%~93.18%。值得一提的是MQTL1和MQTL2，图距仅为2.42 cM和3.22 cM，且分别由9个和20个原始QTL聚合而成，有较高的研究价值。将FABP3、MYPN和ANK1基因映射到整合图谱，分别定位在MQTL5、MQTL12和MQTL16区间内，距离中心位置5.70 cM、3.67 cM和2.49 cM，可将这些区间作为关键区域，开展基因精细定位和挖掘工作。

Meta-Analysis of Tenderness QTL in Swine

This study was conducted for the Quantitative Trait Loci （QTL） related to tenderness to estimate the number and refine the positions of QTL with Meta-analysis. Tenderness QTL were collected and projected to the swine linkage map of USDA-MARC 2.0 to establish an integrated map. Meta-QTL （MQTL） was obtained by meta-analysis which reduced the the 95% confidence interval. Positions of candidate genes and meta-QTL obtained in this study were compared to reckon the precision of meta-QTL. With the software BioMercator 2.1, 99 tenderness QTL were collected from 23 published papers since 2001 and art integrated map was established. 16 meta-QTL as well as their corresponding markers were obtained. The 95% confidence intervals of meta-QTL, with 8 of which were shrunk more than 50% and 6 of which were less than 10 cM, ranged from 2.42 cM to 25.18 cM. The 95% confidence interval of MQTL1 and MQTL2 was only 2.42 cM and 3.22 cM, and was merged with 9 and 20 initial QTL, respectively. Projected to the integrated map, the position of FABP3, MYPN and ANK1 gene was in the confidence interval of MQTL5, MQTL12 and MQTLIL6. These results could lead to more precise QTL position estimates, and offered a basis for gene mining and molecular breeding in swine.