Fine Mapping

Abstract

The ultimate aim of molecular genetic studies of quantitative genetic variation is to find the genes that influence the trait. However, the use of MAS does not require the gene to be known, but can be effective with linked markers. So, the critical point is how closely a QTL is mapped with respect to the markers. Several simulation studies have shown that for MAS, informative markers that flank a QTL within 5 cM seem adequate. In contrast, virtually all QTL-mapping studies have been conducted with panels of 100–300 markers covering the entire genome, corresponding to an average distance between markers of ∼5 and 20 cM. Hence, it is imperative to fine map at least those QTL regions with more number of markers. Such mapping process is also referred to as high-resolution mapping.