PSY 352 Lecture Notes - Lecture 9: Twin, Psy, Neuroticism
Document Summary
Promoting breeding between 2 organisms with desirable qualities. Correlate degree of genetic similarity with degree of personality similarity (parent= 50%, grandparent= 25%, cousin= 12. 5%) People with more genetic overlap are more similar in personality genetic basis. Monozygotic = 100% genetically identical, dizygotic = 50% like any other sibling. So, if a trait is heritable & you"re a genetic photocopy, you should be the same in that trait. But if both mz & dz are similar in something, it"s probably not heritable. Problems: don"t account for environment & identical twins spend more time together, have similar friends, etc. Study similarities between adopted kids and their biological/adoptive parents. Really shows whether something is because of genes or environment. Job preferences (non-adopted: 71% to parents, adopted: 3%) Mz smokes = 16x more likely that twin also smokes. System by which genes are activated/silenced by environment. Ex: rats born to nurturing mother but raised by non-nurturing, gene turned off.