Genetic Similarity

studies

1. Hil et al.(2018)-using DNA to predict intelligence, kinship study


2. Bouchard and McGu(1981)e-heritability of intelligence, twin studies


3. Scarr and Weinburg (1983)-adoption study

what is genetic similarity(intro paragraph)

Genetic similarity is a measure of genetic relatedness among individuals. Behavioural geneticists study the similarity of individuals who share genes and environments to different degrees to quantify heritability. Heritability is a statistic used to measure how much of a variation in a trait(like intelligence) is due to a variation in genes. Heritability is measured as a value between 0 and 1 and is converted into a percentage. The higher the heritability, the more likely that the variation in the trait is due to genetics.

intro to family(kinship) studies

A variety of methods can be used to investigate genetic similarities and how they can influence behaviour. One of these methods is family studies(kinship studies). Family studies are based on collecting data about families on a broader scale, spanning several generations. The level of genetic relatedness is then compared to the observed similarities in a certain trait or behaviour. For example, assuming heritability of a trait, we might expect children to be more similar to their parents than to their grandparents, more similar to siblings than cousins, and so on. 

intro to twin studies

A variety of methods can be used to investigate genetic similarities and how they can influence behaviour. One commonly used method is twin studies. Twin studies are based on comparing the similarity between monozygotic(MZ) twins to the similarity between dizygotic(DZ) twins, for a particular trait or behaviour. MZ twins share 100% of their genotype(genes), and DZ twins share on average 50%. If a behaviour is genetically inherited, one might expect that MZ twins will be more similar to each other in terms of this behaviour than DZ twins. 

potential SAQs

1. explain how genetic similarity can influence one behaviour
2. describe one twin study used to investigate genetic similarity
3. explain how kinship studies are used to investigate genetic similarity
4. describe one piece of research regarding the influence of genetic similarities on behaviour

potential ERQs

1. discuss how genetic similarities may influence behaviour
2. to what extent do genetic similarities influence behaviour