is an observational study that compares DNA across the in people with a disease or trait to people without the disease or trait.
is the complete set of genes or genetic material present in a cell or organism.
Geneticor are bits of DNA (i.e. the four DNA bases – A, C, G, and T) that vary from person to person.
behaviour in this study is defined as reporting sexual relationships only with someone of the opposite sex.
behaviour in this study is defined as having ever had a sexual relationship with someone of the same sex.
refers to a person’s genetic material; the set of genes that they carry.
Aindicates the degree and type of relationship between two variables.
Ais a study in which identical and nonidentical twins are used to obtain an estimate of the of a trait. Identical twins are genetically identical, whereas nonidentical twins are only 50% genetically similar. Any difference in similarity of identical vs similarity of nonidentical twin pairs can therefore be attributed to genetics.
We say that a characteristic/behaviour isif a proportion of individual differences in the trait is due to genetic differences between individuals.
is the proportion of variation in a population trait (in this study, sexual orientation) that can be attributed to inherited genetic factors