Association Mapping in Plants

The phenotypic diversity of many important traits in plants is influenced by several loci, environmental factors and their interactions. Association mapping is one of the methods proposed in recent decades for genetic study and detection of quantitative trait loci (QTLs). Association mapping was used in human genetics and qualitative traits (such as diseases), but recently its use is increasing in the plant science because of advances in high throughput genomic technologies, interests in identifying novel and superior alleles, and improvements in statistical methods. Association mapping through linkage disequilibrium analysis is a purposeful method for identifying marker alleles and quantitative traits association. Unlike linkage mapping, this method identifies the association between phenotypic and polymorphic diversity in the genome by exploiting the diversity of natural populations and taking into account all the events that occurred during the evolution and is a promising approach for overcoming the limitations of linkage mapping. Despite association mapping has high statistical power, the application of this method in structured populations, species with low level of linkage disequilibrium and in traits controlled by rare alleles is complicated and difficult. In this review, we will present a comprehensive view, its application in population, current status and limitation of association mapping in plant science.