Complex Genetic Traits, Heritability, and DNA Profiling

  • Polygenic traits

    • influenced by more than one gene

  • Quantitative traits

    • actions of many genes interacting with the environment

    • shows continuous variation

  • Nature vs Nurture

    • nature

      • genetic

    • nurture

      • environmental

  • Heritability

    • the amount of variation for a trait in a population that can be explained by differences in genes among individuals

  • Natural experiment

    • one factor is naturally removed

  • Epigenetics

    • study of changes in phenotypes caused by changes in gene expression rather than changes in DNA sequence

  • Individual differences

    • heritability does not tell us about individual differences

  • Implicit bias

    • subconscious framework affecting out feelings and based on our physical observation

      • wrongful convictions

      • stereotypes

  • DNA profiling

    • technique used to differentiate DNA sequences to positively identify individuals

  • Polymerase chain reaction

    • process to amplify the DNA sequence

    • each sample, the amount of DNA doubles

    • Thermal cycler

      • automated machine cycles test tubes through periods of heating and cooling

        • heat denatures DNA

          • breaks hydrogen bonds of double helix and forms two individual DNA strands

  • Taq polymerase

    • special heat-tolerant enzyme

  • Gel electrophoresis

    • size-based separation of DNA fragments using electric current