Dorret I. Boomsma (born 18 November 1957, in Huizen, The Netherlands) is a Dutch biological psychologist specializing in genetics and twin studies.

Twin studies[2] provide a way to understand how genotype affects an observable characteristic (called a phenotype).

Boomsma has been a pioneer in collecting a broad spectrum of data (e.g., medical histories, IQ tests, MRI scans) and biological material (e.g., DNA and RNA samples, blood and urine samples) from thousands of twins and analyzing them to determine the role of genetics in characteristics as varied as adult height, brain volume, intelligence, migraine headaches, anxiety, drug addiction, and love of coffee.

Her results span a wide range of behavioral characteristics, including discovery of the surprisingly large genetic component to feelings of loneliness,[3] the fact that first borns have higher IQs than their younger siblings,[4] and the increased influence of genetics on body weight as children grow older.

Due to the large amount of money and complete lack of bureaucracy and restrictions, these were extremely competitive, with a very strong applicant pool and a 13% acceptance rate.