CIE AS/A Level Biology -19.2 Genetic technology applied to medicine- Study Notes- New Syllabus
CIE AS/A Level Biology -19.2 Genetic technology applied to medicine- Study Notes- New Syllabus
Ace A level Biology Exam with CIE AS/A Level Biology -19.2 Genetic technology applied to medicine- Study Notes- New Syllabus
Key Concepts:
- explain the advantages of using recombinant human proteins to treat disease, using the examples insulin, factor VIII and adenosine deaminase
- outline the advantages of genetic screening, using the examples of breast cancer (BRCA1 and BRCA2), Huntington’s disease and cystic fibrosis
- outline how genetic diseases can be treated with gene therapy, using the examples severe combined immunodeficiency (SCID) and inherited eye diseases
- discuss the social and ethical considerations of using genetic screening and gene therapy in medicine
Advantages of Using Recombinant Human Proteins in Disease Treatment
🌱 Introduction
- Recombinant human proteins are made using genetic engineering.
- They are used to safely and effectively treat diseases caused by missing or defective proteins.
🔬 Advantages
- Reduced Risk of Disease Transmission: Made in controlled systems like bacteria or mammalian cells. Avoids contamination from human donors, such as viruses.
- Consistent Supply and Purity: Can be produced in large quantities. Ensures consistent quality and correct dosage for patients.
- Treatment of Genetic Disorders: Provides functional proteins that patients are missing or that are defective.
- Insulin: Treats diabetes; recombinant insulin is identical to human insulin, improving blood sugar control.
- Factor VIII: Treats hemophilia A; reduces risk of bloodborne infections compared to plasma-derived factor.
- Adenosine Deaminase (ADA): Treats SCID; restores immune function.
- Reduced Allergic or Immune Reactions: Human recombinant proteins closely mimic natural human proteins. Causes fewer immune reactions compared to proteins from animals.
🧠 Key Takeaways
Recombinant human proteins are safe, reliable, and highly effective.
They reduce risks from donor-derived proteins.
Successfully used to treat diabetes, hemophilia, and immune deficiencies.
Recombinant human proteins are safe, reliable, and highly effective.
They reduce risks from donor-derived proteins.
Successfully used to treat diabetes, hemophilia, and immune deficiencies.
Advantages of Genetic Screening
🌱 Introduction
- Genetic screening tests people for specific genes or mutations that can cause inherited diseases.
- It helps in early detection, prevention, and making informed choices about health and family.
🔬 Advantages
- Early Detection and Prevention: Finds people at high risk of certain diseases before symptoms appear. Example: BRCA1 and BRCA2 testing helps detect women at risk of breast cancer early so they can take preventive steps.
- Informed Family Planning: Couples can make smart decisions if they carry genes for inherited disorders. Example: Cystic fibrosis testing helps parents know the risk for their children.
- Personalized Medical Care: Treatments and monitoring can be customized based on genetic risk. Example: People with BRCA mutations can choose extra screening or preventive surgery.
- Predicting Disease Onset: Can show the likelihood of developing diseases later in life. Example: Huntington’s disease testing indicates future risk.
- Reducing Disease Burden: Early knowledge helps reduce the impact of diseases. Healthcare systems can plan preventive programs better.
🧠 Key Takeaways
Genetic screening is useful for early detection, personalized care, and informed decisions.
Examples include cancer (BRCA1/BRCA2), neurodegenerative disease (Huntington’s), and inherited disorders (cystic fibrosis).
Supports both personal health management and family planning.
Genetic screening is useful for early detection, personalized care, and informed decisions.
Examples include cancer (BRCA1/BRCA2), neurodegenerative disease (Huntington’s), and inherited disorders (cystic fibrosis).
Supports both personal health management and family planning.
Gene Therapy for Treating Genetic Diseases
🌱 Introduction
- Gene therapy involves inserting, replacing, or repairing defective genes in a patient’s cells to treat or prevent disease.
- It targets the underlying genetic cause rather than just the symptoms.
🔬 How Gene Therapy Works
- Identify the defective gene causing the disease.
- Deliver a functional copy of the gene into patient cells using a vector (often a virus).
- The new gene is expressed, producing the missing or faulty protein.
- Treated cells restore normal function, alleviating the disease.
Examples
- Severe Combined Immunodeficiency (SCID)
- Caused by mutations affecting immune system function.
- Treatment: Functional gene inserted into patient’s immune cells ex vivo, then returned to the patient.
- Outcome: Restores immune function, allowing the patient to fight infections.
- Inherited Eye Diseases
- Certain retinal disorders are caused by defective genes in photoreceptor cells.
- Treatment: Functional gene delivered directly to retinal cells via viral vector.
- Outcome: Restores light-sensitive protein production, improving vision.
🧠 Key Takeaways
Gene therapy targets the root genetic cause of disease.
Uses vectors to deliver functional genes into patient cells.
Effective in diseases like SCID and inherited retinal disorders, with potential for broader applications in genetic medicine.
Gene therapy targets the root genetic cause of disease.
Uses vectors to deliver functional genes into patient cells.
Effective in diseases like SCID and inherited retinal disorders, with potential for broader applications in genetic medicine.
Social and Ethical Considerations of Genetic Screening and Gene Therapy
🌱 Introduction
- Genetic screening and gene therapy offer powerful tools for diagnosing and treating genetic diseases.
- However, they raise important social and ethical issues that must be carefully considered.
🔬 Social Considerations
- Access and Equity: Advanced genetic technologies can be expensive. There is a risk that only wealthy individuals or countries may benefit, creating inequality in healthcare access.
- Psychological Impact: Knowledge of genetic risk can cause anxiety, stress, or altered life choices. Example: Positive test for BRCA1/BRCA2 may lead to difficult decisions about preventive surgery.
- Impact on Family and Society: Genetic information affects not just individuals but also family members who may share the risk. Could influence career, insurance, or social relationships.
🔬 Ethical Considerations
- Informed Consent: Patients must fully understand the risks and benefits of genetic tests or therapies. Ethical practice requires voluntary participation.
- Privacy and Confidentiality: Genetic information is highly personal and must be protected. Misuse could lead to discrimination by employers or insurance companies.
- Gene Therapy Risks: Potential for off-target effects or unintended mutations. Long-term safety is still under investigation, raising questions about responsibility and liability.
- Germline Modifications: Editing genes in embryos affects future generations, raising ethical concerns. Could lead to debates about “designer babies” and human enhancement.
- Social Pressure and Stigmatization: Individuals may feel pressured to undergo screening or therapy. Could create stigmas against people with untreated genetic conditions.
🧠 Key Takeaways
Genetic technologies have great medical potential, but must be used responsibly.
Ethical use requires informed consent, privacy protection, and consideration of long-term societal impacts.
Balancing benefits and risks is essential to ensure fairness, safety, and respect for human rights.
Genetic technologies have great medical potential, but must be used responsibly.
Ethical use requires informed consent, privacy protection, and consideration of long-term societal impacts.
Balancing benefits and risks is essential to ensure fairness, safety, and respect for human rights.