A Comparison of Two Statistical Tests for Interaction in Genetic Data

This paper focuses on statistical methods that test for the effect of a single gene in a way that accounts for interaction with other genes. Such tests of association can be difficult since there may be many genetic and environmental factors that contribute to an effect. A gene is a hereditary DNA sequence that codes for a specific protein. A locus is a gene’s location in the DNA sequence of nucleotides (A, T, G, and C) and an allele is a specific version of a gene that has multiple forms. The existence of interactions between loci makes it difficult to determine the effect of a single genetic factor. Gene-gene interaction occurs when two genes together affect how a trait is expressed. That is, their combined effect is not the same as the sum of the two genes’ individual effects. If there are multiple genes that effect a genetic trait, then examining a gene in isolation without allowing for interactions may result in missing the gene’s effect. This is why allowing for interaction in a test of association can be more successful than tests that do not allow for interaction