鸡脂肪酸合成酶基因多态性与生长和体脂性状的相关研究

Polymorphisms of Fatty Acid Synthase Gene Associated with Growth and Fatness Traits in Chickens

试验以东北农业大学肉鸡高、低脂双向选择品系为试验材料,根据GenBank公布的鸡脂肪酸合成酶基因（FAS基因）的序列设计引物,用测序的方法进行多态性检测。结果检测到2个多态性位点,一个是位于序列769bp处的A769T位点,一个是位于1418~1424bp处的7bp插入/缺失位点。用PCR-SSCP和PCR-LP的方法对上述2个多态性位点进行基因型分型,2个多态性位点在研究群体中都检测到了3种基因型,其中A769T位点产生的3种基因型分别命名为AA、AB和BB,7bp插入/缺失位点产生的3种基因型分别命名为CC、CD和DD。根据研究群体的特点,建立合适的统计分析模型进行不同基因型与生长和体脂性状的相关分析。统计分析结果表明,鸡FAS基因的A769T位点对鸡的腹脂重和腹脂率有显著影响（P〈0.05）,AB基因型个体的腹脂重和腹脂率显著低于AA基因型个体;7bp插入/缺失位点对7周龄体重有一定影响（P〈0.2）,CD基因型个体的7周龄体重显著高于CC基因型个体。初步推测FAS基因可能是控制鸡体重和脂肪沉积的主效基因或与主效基因紧密连锁。

In this study , the Northeast Agricultural University high and low fat （ NEAUHLF ） broiler lines were used as materials. Primers for fatty acid synthase （FAS） gene were designed according to the database of chicken genomic sequence. The polymorphisms were detected by DNA sequencing , and PCR-LP , PCR-SSCP methods. Two polymorphisms were found , A769T and 7 bp Insert/Deletion （ I/D ） at 1418 to 1424 bp. Correlation analysis between the polymorphismsof the FAS gene with growth and fatness traits in the population was carried out using the appropriate statistical model. The results showed that the A769T polymorphism was related to abdominal fat traits , the birds with AB genotype had significant lower （P 〈0.01 ） abdominal fat weight and abdominal fat percentage than the birds with the AA genotype （P〈 0.01 ） . The 7 bp I/D polymorphism was related to the body weight at 7 weeks of age （P〈 0.2 ）, and the birds with the CD genotype had much higher body weight than the birds with the CC genotype. From these results , it concluded that polymorphisms found in FAS gene could be or link to a major gene that affected growth and fatness traits in chickens.