Question

Genome-wide association studies have identified many genomic loci at which the presence of one or more SNPs is associated with altered risk of a particular disease. Almost all of these SNPs have a very small influence on risk of the corresponding disease, typically with effect sizes of less than 1.5. What does it mean to have an effect size of less than 1.5?

Answer 1

SNPs represent the single-nucleotide polymorphism sites in individuals of same species which confers them either a benefit or deleterious effect with respect to a stressor/stimulus. In this regard, the presence of SNPs has been very extensively exploited to develop therapeutic strategies which are targeted to delineate the deleterious effects arising due to SNPs. Hence, the comparative analysis of SNP between affected and unaffected individuals is usually made in order to develop a therapeutic strategy.

In this regard, it is important to understand that an SNP based study is made by counting the large population size and normalizing this data with the number of SNPs observed. Thus, the final fraction generally comes out to be nearly 1.3-1.7 or nearly 1.5. This means that every time an SNP arrives in the genome at a partticular location, it is likely by 1.5 times that it will produce a pathological effect.