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What is concordance?
A statistical measure used to determine the likelihood that certain traits have a genetic basis. Based on the similarities between twins in twin studies.
What are twin studies?
Monozygotic twins - identical - share 100% of genes
Dizygotic twins - Non-identical - share 50% of genes
Comparison of monozygotic and dizygotic twins to determine if there is a genetic basis for a behaviour/characteristic
What is a genotype?
The whole genetic makeup of an individual
What is a phenotype?
A set of observable characteristics that come as a result of interaction between the genotype and the environment
Important note: biological approach isn't fully naïve in that it acknowledges depends both on Genetics and how they interact with the environment.
How can genetic factors be determined based on data?
If you have a group of identical twins, you can compare the concordance rates of a target trait (the proportion of the sample that share the trait in both identical twins).
If there is a significant proportion of pairs sharing a certain trait, you may conclude that there is a genetic factor at play.
Otherwise, there probably isn't much of a factor at play and you may suggest other factors.