Genetic epidemiology

thumb|right|160px|Studies of heritability ask questions such as to what extent do genetic factors influence differences in height between people. This is not the same as asking to what extent do genetic factors influence height in any one person. Heritability is a statistic used in the fields of breeding and genetics that estimates the degree of variation in a phenotypic trait in a population that is due to genetic variation between individuals in that population. The concept of heritability can be expressed in the form of the following question: "What is the proportion of the variation in a g

DNA locus associated with variation in a quantitative trait

examination of many genetic variants in different individuals to see if any variant is associated with a trait

statistical method in genetic epidemiology

study of the role of genetic factors in determining health and disease

response to the same environmental variation differently by different genotypes

Dependence of environmental conditions on individual genotype