the analysis of quantitative variation in natural populations with isofemale strains定量分析与isofemale株自然种群的变化.pdf

The analysis of quantitative variation in natural populations with isofemale strains A.A. HOFFMANN P.A. PARSONS Department of Genetics and Human Variation, La Trobe University, Bundoora 3083, Victoria, Australia Summary Isofemale strains are having an increasing role in the analysis of variability of ecological and behavioural traits in natural This therefore considers the association between populations. paper heritability and phenotypic variation within and between isofemale strains. Heritability from an isofemale strain analysis approximates narrow heritability over a wide range of dominance values, particularly when genes contributing to variation in a trait are at intermediate frequencies. Meaningful heritability estimates require that isofemale strains are maintained at a population size greater than 50 and tested within 5 generations after establishment. Values of heritabilities for morphological traits in Drosophila melanogaster were similar to those estimated from a conventio- nal sib analysis. Published data on isofemale strains can therefore be put into a theoretical framework. The contribution of isofemale strain analyses to the debate about the number of loci affecting variation in quantitative traits is briefly discussed. Keys words : isofemale strain, heritability, Drosophila melanogaster, gene number, morphologi- cal trait. Résumé Analyse de la variabilité quantitative dans des populations naturelles par des lignées isofemelles Les lignées isofemelles jouent un rôle croissant dans l’analyse de la variabilité des car