摘要
采用计算机模拟数据和数量性状基因作图的双侧标记基因型均值回归方法 ,研究了分子标记密度、性状遗传力和样本容量 3因素对 F2 群体数量性状基因图谱构建的影响。结果表明 :( 1)在 QTL被发现的能力上 ,适当大 (标记间距 15c M)的标记密度较有利于 QTL的检测 ,过大或过小均不利 ;随着遗传力提高和样本容量变大发现 QTL的能力提高 ,但效率下降。为此可以给出一定保证度下的最适标记密度和样本容量 ,以减少试验成本。如 QTL的遗传力 10 %、标记间距 15c M,则样本容量 30 0就可保证 QTL的发现能力达 80 %以上。 ( 2 )在 QTL位置和效应估计上 ,只要标记间距不过大 (如 50c M) ,一般来说 ,一旦 QTL能被检测到 ,则其位置和效应的估计也较准确 ,其位置估计值的 95%置信区间绝大多数在 2 0 c
The power of detection and accuracy of QTL mapping in different marker densities, heritabilities and sample size were studied by the simulated data of F 2 population and mean regression method of flanking marker genotypes. The results showed: (1) The power of QTL detected had significant difference in different marker densities. The optimum distance of flanking markers was 15 cM. The increase of heritability and sample size can enhance the power of detecting QTL, but the efficiency decreased. From this result, the optimum marker density and sample size can be formulated under definite power of detection of QTL. For instance, the heritability of a QTL was 10% and the marker density was 15 cM, F 2 population of 300 individuals can ensure the power of detecting QTL high 80%. (2) In general, only if the distance of flanking markers was not larger than 50 cM, the accuracy of estimates of QTL position and effects was very high. The confidence intervals of 95% of QTL position was less than 20 cM.
出处
《作物学报》
CAS
CSCD
北大核心
2001年第4期469-475,共7页
Acta Agronomica Sinica
基金
国家自然科学基金项目(批准号 :3990 0 0 80 )
农业部95生物技术项目资助
关键词
数量性状基因
样本容量
计算机模拟
作图精度
基因图谱
分子标记
性状遗传力
作物
Quantitative trait loci
Marker density
Heritability
Sample size
Computer simulation
Power of detection and accuracy of QTL mapping
