Imputation (genetics)

Imputation in genetics refers to the statistical inference of unobserved genotypes. It is achieved by using known haplotypes in a population, for instance from the HapMap or the 1000 Genomes Project in humans, thereby allowing to test initially-untyped genetic variants for association with a trait of interest. Genotype imputation hence helps tremendously in narrowing-down the location of probably causal variants in genome-wide association studies.