Genetics Chapter 11 Objectives

Chapter 11 Objectives

• Discuss family history as a predictor for disease risk.
• Identify appropriate uses of DNA testing and explain how such tests might lead to genetic discrimination.
• Define genetic engineering and explain why cloning and stem cell research are controversial issues.
• Explain three possible remedies for couples experiencing infertility problems.
• List laws affecting healthcare that pertain especially to children's rights.

Vocabulary

• Heredity: the process by which genetic traits are passed from one generation to the next.
• Genetics: the science that accounts for the differences and similarities among living things.
• DNA (deoxyribonucleic acid): the molecule that makes up chromosomes.

Figure 11.1

• Shows the cell nucleus containing 23 pairs of chromosomes.
• Chromosomes contain genes, which are made up of DNA bases.
• The DNA strand is a double helix structure.

DNA

• The relationship between inherited DNA and disease is scientifically confirmed.
• Family history is a key risk factor for various diseases (cancer, cardiovascular disease, diabetes, etc.).
• Cultural and socioeconomic factors from family also influence health risks.
• Forty-six chromosomes (23 pairs) are found in every human cell nucleus (except egg and sperm cells which have 23).
• Chromosomes carry genes responsible for human characteristics (eye, skin, hair color, height etc.)
• The human genome is all the genetic information necessary to form a human being.
• Humans have approximately 20,000 to 25,000 genes.

Testing DNA

• Predictive testing: used to determine if harmful genes leading to hereditary diseases are present.
• Carrier testing: to determine if an individual carries harmful genes that can be passed on to offspring.

More Testing

• Prenatal testing: used to identify genetic disorders in utero. Methods include ultrasound, amniocentesis, chorionic villus sampling and maternal blood tests.
• Preimplantation testing: examines embryos for harmful genes before implantation to prevent passing those genes to offspring.

And More Testing

• Forensic testing: used in law enforcement to identify suspects or victims.
• Tracing lineage: used to determine parentage and relationships.
• Newborn screening tests: check for treatable genetic conditions.
• Diagnostic testing: confirms a diagnosis, including genetic diseases.
• Medical treatment determination: helps determine appropriate medication and dosing for a patient based on their genes.

Genetic Disease

• Permanent changes in DNA (mutations) often cause genetic diseases.
• Mutations can affect a single gene or multiple genes, and environmental factors can trigger diseases with more than one gene.
• Some genetic diseases involve abnormalities in the structure or number of entire chromosomes (e.g., Down syndrome).
• Genetic counseling supports individuals facing genetic testing results/issues.

Genetic Discrimination

• Increased ability to identify genetic differences raises concerns about the appropriate use of information.
• Genetic discrimination describes the differential treatment of individuals based on their actual or presumed genetic differences.
• Genetic Information Nondiscrimination Act (GINA) prevents discrimination in the workplace and by health insurance issuers.
• Other laws protect people from discrimination based on genetic info.

Genetic Engineering

• Genetic engineering involves manipulating genes to transfer desirable characteristics between organisms to other species.
• Used to create organisms with desired characteristics for different applications (cold-tolerant plants, disease-resistant crops etc).

Cloning

• Cloning is the process of creating an exact genetic replica of a cell, tissue, or organism.
• Types of cloning include:
  • Gene cloning: generating multiple copies of a DNA segment.
  • Therapeutic cloning: creating embryonic stem cells to treat diseases.
  • Reproductive cloning: duplicating entire animals.
  • Cloned animals can experience premature aging and complications.
  • Most cloning attempts do not lead to healthy viable offspring.

Exceptions to the Rule

• Cloning for biomedical research in animals has a goal of producing substances useful in medicine (e.g., insulin, growth hormone).
• However ethical questions and public concerns surrounding cloning raise objections about its use, including animal rights violations, and health-related issues and scientific feasibility.

Gene Therapy

• Gene therapy involves inserting a functioning gene into cells with an abnormal or missing gene to treat diseases.
• Gene therapy techniques include special diets, vitamins, or treatments.
• Fetal gene therapy may be possible via in utero cellular therapy (e.g. bone marrow transplantation)
• Germ-line gene therapy faces ethical concerns as it involves changing the genes of sperm/eggs.

Infertility

• Infertility affects about 10-15 percent of couples in the US.
• Common infertility solutions include:
  • In vitro fertilization (IVF): combining eggs and sperm outside the body.
  • Artificial insemination
  • Surrogacy: if a woman cannot carry an embryo to term.

Surrogate/Adoption

• Surrogate mothers agree to carry a child to term for another couple for a fee.
• Adoption is another option for couples who want to raise a child.
• There are legal and ethical considerations for both surrogacy and adoption.

Children's Rights

• Common law and parens patriae establish parents' right to make healthcare decisions for minor children.
• State laws and regulations address children's rights, encompassing conditions and circumstances surrounding newborns and severely disabled children.

Abandonment

• Safe haven laws in all 50 states allow parents to leave newborns in designated locations to protect them from prosecution.