PSY 240 Chapter Notes - Chapter 2: Fragile X Syndrome, Y Chromosome, Phenylketonuria

• School: University of Arizona
• Department: Psychology Main
• Course: PSY 240
• Professor: Rebecca Gomez

Document Summary

2. 4: chromosomal errors: down syndrome: extra 21st chromosome in the ovum, risk increases with maternal age (after age 35), somewhat with paternal age, cognitive disability, short lifespan, heart conditions, and early dementia. 2. 5: using family resemblance to study heredity and environment: behavior genetics, how much variation in a trait is due to genes or to the environment, segregating genes, different alleles, individual differences, twin designs, 100 vs 50% segregation. 2. 6: heritability and shared and non-shared environment: heritability, proportion of variance accounted for by genes (roughly 50%) 2. 7: limitations of behavior genetic studies: challenging to separate genes from environment, genes show different effects in different environments, environments influence gene expression. These factors make it challenging to estimate the relative impact of genes and the environment in producing individual differences. 2. 9: gene-environment transactions: negative environmental effects are seen for only one version of a particular gene (in the example i will show, the short allele).