Genetics #2

Jun 19, 2024

Genetics and Human Behavior Lecture

Introduction

  • Curiosity about family history and genetics.
  • Preventive measures for genetic conditions.
  • Concerns about genetic knowledge causing anxiety.

Genetic Tests (e.g., 23andMe)

  • Tests for genetic predispositions to diseases like Alzheimer’s and Parkinson’s.
  • Ethical considerations of knowing genetic risks without available cures.
  • Impact on mental health: anxiety, fear of self-fulfilling prophecies.
  • Societal shift towards valuing knowledge and control.

Genetic Manipulation and Designer Babies

  • Ethical dilemma: Should we control genetics?
  • Current capabilities: in-vitro fertilization and genetic testing of embryos.
  • Real-world examples: Selecting embryos without genetic diseases.
  • Psychological implications and ethical questions:
    • Manipulating genetics during pregnancy.
    • Potential societal and developmental impacts.

Controversial Scenarios and Ethical Questions

  1. Cancer Prediction
    • Example: High chance of child developing cancer. Would you change the genes?
  2. Depression Prediction
    • Example: High chance of child experiencing severe depression. Would you change the genes?
  3. Down Syndrome Prediction
    • Example: Child with Down Syndrome. Would you change the genes?

The Complexity of Genetic Control

  • Knowledge and control: Is there such a thing as too much?
  • Balance between positive and negative human traits.
  • Who should have the power to manipulate genes?
  • Risks of power misuse (e.g., historical tyrants like Hitler).
  • Socioeconomic disparities: Rich vs. Poor in genetic access.

Genetics and its Interaction with the Environment

  • Genotype vs. Phenotype
    • Genotype: Genetic makeup.
    • Phenotype: Observable characteristics.
    • Environmental influence on gene expression.

Sources of Variability

  • Genetic and environmental variability.
  • The possible role of free will as a third factor.

Dominant vs. Recessive Genes

  • Dominant genes: More likely to be expressed.
  • Recessive genes: Less likely to be expressed unless paired with another recessive gene.

Polygenic Traits

  • Most traits influenced by multiple genes (polygenic).
  • Complex interactions determine traits like height, intelligence, eye color.

Heredity-Environment Interactions

  1. Passive Genotype-Environment Correlation
    • Parent’s genetic predispositions create a certain environment for the child.
  2. Evocative Genotype-Environment Correlation
    • Child’s genetic traits evoke specific responses from the environment.
  3. Active (Niche-picking) Correlation
    • Children seek environments compatible with their genetics.

Bi-Directional Influence: Epigenetic View

  • Genetics and environment influence each other.
  • Examples: Prenatal development, environmental factors impacting gene expression.

Mind Matters: The Role of Free Will

  • Development as a co-construction of biology, culture, and the individual.
  • Present choices influencing future outcomes.

Conclusion

  • Complex interplay of genetics, environment, and individual choice.
  • Genetic understanding should be balanced with ethical considerations and respect for individual variation.

This lecture covers the complexity and ethical implications of genetic knowledge and manipulation, emphasizing the interplay between genetics and environment and the potential role of individual free will in human development.