To date, most marker-trait associations have been revealed using QTL and genome-wide association studies (GWAS), demonstrating both their successes and their limitations. Haplotypes are the particular combinations of alleles/markers observed on a chromosomal segment in a given population, and they make it possible to test multiple allelic interaction effects. Haplotypes can also increase the statistical power of GWAS by reducing the number of tests compared to using all SNPs. Alleles within the same haplotype block are more likely to be inherited together, while sharing a similar minor allele frequency (MAF). Haplotype-based analyses examine groups of SNPs simultaneously rather than individual SNPs, thereby increasing the statistical detection power for many aspects of both population and quantitative genetics, including identifying signals of recent positive selection and performing GWAS, respectively. Haplotype association mapping takes into account not only allelic heterogeneity but also possible statistical interactions among close markers, making it more powerful than single-marker and multiple-marker analysis.
Click here for original story, Multiple haplotype-based analyses provide genetic and evolutionary insights into tomato fruit weight and composition
Source: Phys.org