中文摘要：

垂体腺苷酸环化激酶多肽（pituitary adenylate cyclase-activating polypeptide,PACAP）是一种能够促进生长激素、促性腺激素和催乳素分泌的多效激素,属于胰高血糖素/分泌肽家族的成员。为探索PACAP基因多态性对大口黑鲈（Micropterus salmoides）生长性状的影响,本研究采用直接测序的方法在PACAP基因上检测到一个单核苷酸多态性（single nucleotide polymorphism,SNP）位点：A-2282C,基因型检测共发现3种基因型：AA、AC和CC,其基因型频率分别为0.034、0.645和0.321,A等位基因频率为0.356 3,C等位基因频率为0.643 7。随机选取同批繁殖、同塘养殖的327尾大口黑鲈用Snapshot方法进行SNPs位点检测和分型,构建最小二乘分析模型,分析基因型与生长性状的相关性。χ^2检测结果显示,哈温-平衡常数为0.061 5,即该位点在所检测大口黑鲈群体中基本处于Hardy-Weinberg平衡状态,有效等位基因数（Ne）为1.846 5,期望杂合度（Ho）和观测杂合度（He）分别为0.540 9和0.644 2。方差分析结果显示,AC基因型群体的平均体质量、体高和全长相对于AA基因型群体分别增长了30.6%、10.7%和8.3%,相对于CC基因型群体分别增长了10.5%、4.7%和2.7%;且AC基因型群体在体质量、体高和全长上显著高于AA和CC基因型群体（P〈0.05）。另外,虽然AA基因型群体的平均体质量、体高和全长相对于CC基因型群体分别增长了18.1%、5.8%和5.4%,但AA型群体和CC群体在各生长性状上没有显著差异（P〉0.05）。该位点可能是影响大口黑鲈生长性状的的主效数量性状核苷酸（quantitative trait nucleotides,QTN）或与之紧密连锁,可作为大口黑鲈选育的候选分子标记。

英文摘要：

Pituitary adenylate cyclase- activating polypeptide（PACAP）, a member of glucagon/secretes peptide family, is a pleiotropic hormone that enhances and stimulates the secretion of growth hormone,gonadotropin, prolactin and somatolactin. The single nucleotide polymorphism（SNP） in PACAP gene canaffect its function or translation and transcription. Studying the association between the SNP and growth traits can provide candidate markers for marker- assisted selection. We detected the polymorphism of PACAP gene by DNA sequencing to explore the association between the polymorphism of PACAP and growth traits of largemouth bass（Micropterus salmoides）. Five pairs of primers were designed to amplify the PACAP gene sequence, and a SNP A-2282 C site was found in the 4th intron, and had 3 genotypes named as AA, AC and CC, respectively. The genotype and gene frequency of this SNP in 327 largemouth bass were further assayed with the method of Snapshot, the result showed that gene frequency of genotypes AA, AC and CC were 0.034,0.645 and 0.321, respectively, and the frequency of A allele and C allele were 0.355 8 and 0.644 2. Chi-square test showed that the locus was in Hardy-Weinberg equilibrium in the largemouth bass population,the effective number（Ne） of the locus was 1.846 5, expected heterozygosity（Ho） and observed heterozygosity（He） were0.540 9 and 0.644 2. The least squire method（LSM） was used to analyze the association of genotype with growth traits, and variance analysis indicated the mean values of AC genotype group was higher than that of AA and CC groups in body weight, body length, head length, total length, body depth and caudal peduncle length. And the body width and caudal peduncle length with AC genotype were significantly higher than that of AA（P〈0.05）. The depth with AC genotype was extremely significantly higher than group with CC（P〈0.01）, and those with AC genotype were significantly higher than those with AA genotype（P〈0.05）. The locus can be a candidate molecular