PSYC 2P25 Lecture Notes - Lecture 6: Heritability, Trait Theory, Epistasis

• School: Brock University
• Department: Psychology
• Course: PSYC 2P25
• Professor: Michael Ashton

Document Summary

What proportion of the variation in a personality trait, among people in a given population, is due to: Researchers want to find the heritability (h2) of a trait the proportion of trait variation that is due to heritable (genetic) variation in a given population. Of course, 0 = h2 = 1 (h2 is a proportion) To find the h2 of a trait of a personality trait, we need to know whether (genetic) relatives have similar trait levels beyond any similarity due to their common environments. 1- study many sets of identical (mz) twins raised apart. If the(cid:455)"re raised apart, the(cid:374) si(cid:373)ilarit(cid:455) (cid:271)et(cid:449)ee(cid:374) the(cid:373) (cid:272)a(cid:374)t (cid:271)e due to being raised together. Measure trait, a(cid:374)d fi(cid:374)d (cid:272)orrelatio(cid:374) (cid:894) r (cid:895) (cid:271)et(cid:449)ee(cid:374) t(cid:449)i(cid:374)s le(cid:448)els (cid:894)if t(cid:449)i(cid:374) a is (cid:862)high(cid:863) i(cid:374) trait, is t(cid:449)i(cid:374) b also?) For mz twins raised apart, r indicated heritability: e. g. r = . 60 h2 = . 60.