Association Mapping concepts and types.pptx

association mapping

1. Association Mapping PLINK Software

2. Association Mapping “Association analysis, also known as LD mapping or association mapping, is a population-based survey used to identify trait-marker relationships based on linkage disequilibrium” (Flint-Garcia et al. 2003)

3. Linkage Disequilibrium nonrandom association of alleles at different loci. LD can occur between more distant sites or sites located in different chromosomes LD was firstly described by Jennings in 1917 Quantification of LD developed by Lewtonin in 1964 AM is actually an application of LD

4. Pros AM offers three main advantages over linkage mapping: Mapping resolution, allele number and time saving in establishing a marker-trait association and its application in a breeding program (Flint-Garcia et al., 2003). availability of broader genetic variations with wider background for marker-trait correlations no need for the development of expensive and tedious biparental populations

5. Cons Complicated or unknown patterns of LD The complexity and mode of gene action of the trait of interest. sample size and experimental design. Rare alleles cannot be detected with good confidence, unless the effect is very large.