Professor Dorret Boomsma (born 1957), Professor of Biological Psychology at Amsterdam Vrije Universiteit, will receive the prize for her pioneering work in human behavioural genetics. Her department has built up the Dutch national twins register into one of the largest and most representative twins database in the world. It comprises information on almost 30 thousand identical and non-identical twins. By systematically comparing both types of twins, Professor Boomsma has succeeded in distinguishing the hereditary component in various personality characteristics from environmental factors. She will use part of the prize money to extend the twins register by adding data on other family members.
In the field of cognitive development, Professor Boomsma has discovered that the hereditary component of a childs IQ rises sharply during its first years at school. This means that the genetic expression of the properties which help determine intelligence takes place at a relatively late stage.
However, some hereditary factors that influence the development of behavioural and emotional problems are expressed very early in life. In three-year-old children, for example, the influence of heredity on such things as anxiety, introversion and over-active behaviour is very great. It is only as the child grows up that the parental environment begins to play a modest role in these problems.
One interesting discovery made by Professor Boomsma is that the genetic influences on variation in the number of cigarettes smoked was just as great as for the variation in cholesterol levels.