what is a QTL
A quantitative trait locus (QTL) is a section of DNA (the locus) that correlates with variation in a phenotype (the quantitative trait).The QTL typically is linked to, or contains, the genes that control that phenotype.he simplest method for QTL mapping is analysis of variance (ANOVA, sometimes called marker regression) at the marker loci. In this method, in a backcross, one may calculate a t-statistic to compare the averages of the two marker genotype groups.