[2] It is closely allied to both molecular epidemiology and statistical genetics, but these overlapping fields each have distinct emphases, societies and journals.
"[4] As early as the 4th century BC, Hippocrates suggested in his essay "On Airs, Waters, and Places" that factors such as behavior and environment may play a role in disease.
John Snow is considered to be the father of epidemiology, and was the first to use statistics to discover and target the cause of disease, specifically of cholera outbreaks in 1854 in London.
More recently, the scope of genetic epidemiology has expanded to include common diseases for which many genes each make a smaller contribution (polygenic, multifactorial or multigenic disorders).
This has developed rapidly in the first decade of the 21st century following completion of the Human Genome Project, as advances in genotyping technology and associated reductions in cost has made it feasible to conduct large-scale genome-wide association studies that genotype many thousands of single nucleotide polymorphisms in thousands of individuals.