Genetic Testing Overview

Study Notes

Genetic testing analyzes DNA to determine if a person carries a genetic disease or has a predisposition for one.
Genetic testing can be used for prenatal screening, carrier screening, pre-implantation testing, and population screening.
Carrier screening determines if someone carries a mutated gene which is different from having the disease.
Prenatal screening tests are done during pregnancy to assess fetal health.
Pre-implantation testing screens embryos for genetic diseases before implantation in IVF.
Population screening looks for genetic diseases within a specific population.
Genetic counselors help patients understand testing results and make informed decisions.
Ethical considerations include privacy concerns and access to testing.
Specificity measures the accuracy of a negative test whereas sensitivity measures the accuracy of a positive test.

The FDA ensures the safety and effectiveness of drugs before they are approved for use.
Clinical trials assess the safety and efficacy of new drugs using different phases:
- Phase 1: safety testing in a small group of healthy individuals.
- Phase 2: effectiveness testing in a larger group of individuals with the disease.
- Phase 3: large-scale trials to confirm effectiveness and monitor side effects.
- Phase 4: post-market surveillance to monitor long-term safety and effectiveness.

Gene therapy replaces or alters mutated genes to treat diseases.
There are two main types:
- Somatic gene therapy targets specific cells and does not pass down to offspring.
- Germ-line gene therapy targets reproductive cells and can be passed down to future generations.
Somatic gene therapy can be administered through vectors like viruses or directly.
Germ-line gene therapy faces ethical concerns due to the potential for unintended consequences.
Vectors are used to deliver therapeutic DNA into cells.
Gene therapy is expensive due to research and development costs.
Gene therapy is a relatively new and evolving field.

A GMO is an organism that has been genetically modified to alter its traits.
Recombinant DNA involves combining DNA from different sources.
Cloning in bacteria makes copies of a gene to produce a protein of interest.
Transgenic organisms have genes from different species introduced into their DNA.
Pharming uses genetically modified animals to produce pharmaceuticals.
rBGH is a genetically modified growth hormone produced by bacteria.
Bt gene produces a pesticide that kills insects.
Roundup Ready soybeans produce a protein that makes them resistant to herbicides.
Genetic modification in plants can provide benefits like increased yields, improved nutritional value, and pest resistance.
The USDA regulates genetically modified foods in the US.

Blood carries oxygen, nutrients, and hormones throughout the body.
Blood is composed of:
- Plasma: fluid component
- Formed elements: cells (red blood cells, white blood cells, platelets)
- Red blood cells transport oxygen, contain hemoglobin.
- White blood cells fight infections.
- Platelets help in clotting.
Blood cells are produced in the bone marrow via hematopoiesis.
Oxyhemoglobin carries oxygen, deoxyhemoglobin releases it.
Malaria causes anemia by destroying red blood cells.
Blood transfusions must match blood types to avoid complications.
Rh-negative mothers may receive RhoGAM during pregnancy to prevent complications.
Blood clots form through a complex process involving platelets and clotting factors.
Anticoagulants are medications used to prevent blood clotting.