IB MYP 4-5 Biology-Genome mapping and application- Study Notes - New Syllabus
IB MYP 4-5 Biology-Genome mapping and application- Study Notes – New syllabus
IB MYP 4-5 Biology-Genome mapping and application- Study Notes – IB MYP 4-5 Biology – per latest IB MYP Biology Syllabus.
Key Concepts:
- Human Genome Project
- Personalized medicine
- Gene therapy
- Pharmacogenomics
Genome Mapping & Human Genome Project
What Is Genome Mapping?
Genome mapping is the process of identifying the location of genes on a chromosome – like marking cities on a map.
It helps scientists understand which genes control traits, where mutations happen, and how genes interact.
Key Terms
| Term | Meaning |
|---|---|
| Gene | A section of DNA that codes for a protein |
| Genome | The complete set of DNA in an organism |
| Mapping | Finding the exact location of genes |
| Sequencing | Reading the order of DNA bases (A, T, C, G) |
The Human Genome Project (HGP)
A global scientific project launched in 1990 and completed in 2003, aimed at decoding the entire human DNA – about 3 billion base pairs long.
It was like writing the first full instruction manual of the human body.
Goals of the Human Genome Project
- Identify all human genes (approx. 20,000–25,000)
- Understand their functions
- Store data in accessible public databases
- Improve sequencing and data tools
- Address ethical, legal, and social issues (ELSI)
Achievements of the HGP
| Success | Explanation |
|---|---|
| Mapped all human genes | Around 99% of the genome was sequenced |
| Identified disease genes | Helped find causes of genetic disorders |
| Created large databases | Open access for scientists worldwide |
| Encouraged collaboration | Involved teams from USA, UK, Japan, India, and others |
| Boosted biotech innovation | Led to new methods in gene therapy and diagnostics |
Applications of Genome Mapping
| Field | Application Example |
|---|---|
| Medicine | Identify genes linked to diseases (e.g., cancer, diabetes) |
| Drug development | Personalized medicine based on DNA |
| Prenatal testing | Detect disorders in unborn babies |
| Agriculture | Breed high-yield, pest-resistant crops |
| Evolutionary biology | Trace evolution by comparing species’ genomes |
Ethical Issues Raised by HGP
- Genetic privacy: Who owns your DNA data?
- Employment discrimination: Could employers misuse genetic information?
- Insurance bias: Could people be denied coverage based on genes?
- Mental stress: Knowing future risks may cause anxiety
These concerns are addressed by the ELSI (Ethical, Legal, and Social Implications) program.
Personalized Medicine
Personalized medicine is a modern medical approach where treatments are tailored to each person’s genetic makeup, lifestyle, and environment. Instead of “one-size-fits-all,” doctors can now predict how your body will respond to a drug or disease before even starting treatment.
Why Genes Matter in Medicine?
– Each person’s DNA is unique
– Your genes affect how your body reacts to medicines, diseases, and food
– Some people may get side effects from a drug, while others are fully cured – because of differences in their genes
How Personalized Medicine Works?
| Step | What Happens |
|---|---|
| Genetic Testing | DNA is tested to find useful genetic information |
| Analysis | Doctors look for disease risks or drug sensitivity |
| Customized Plan | Right medicine, right dose, right time – made just for you |
Real-Life Applications
| Area | Example |
|---|---|
| Cancer treatment | Targeted therapies for breast, lung, or colon cancer |
| Drug response | Some people need higher/lower doses of common medicines |
| Rare diseases | Finding the exact gene causing inherited conditions |
| Vaccine response | Gene-based insights during COVID-19 vaccine trials |
Benefits of Personalized Medicine
Saves money: Avoids trial-and-error treatments
More effective treatment: Medicine matches the patient’s biology
Faster diagnosis: Early detection using genetic clues
Fewer side effects: Avoids drugs that won’t work or cause harm
Better prevention: Helps identify risk and act early
Ethical and Practical Concerns
| Concern | Explanation |
|---|---|
| Privacy of DNA data | Genetic information could be misused |
| Unequal access | Expensive tests may not be available to everyone |
| Discrimination risk | Employers or insurers could use DNA data unfairly |
| Mental stress | Knowing about future diseases may cause anxiety |
Personalized Medicine in India
- Still in early stages
- Used mostly in cancer treatment and rare disease diagnosis
- Government and private labs are developing affordable tests
- Needs more awareness and healthcare infrastructure
Gene Therapy
Gene therapy is a treatment where healthy genes are inserted into a person’s cells to replace, fix, or silence faulty ones that cause disease.
Instead of using medicines to treat symptoms, gene therapy aims to correct the actual genetic defect.
How Does It Work?
| Steps | Explanation |
|---|---|
| 1. Identify faulty gene | Doctors find which gene is causing the illness |
| 2. Prepare a healthy gene | A normal copy of that gene is made in the lab |
| 3. Deliver it into cells | The new gene is added using a vector (usually a virus) |
| 4. Cells start using the new gene | The healthy gene helps restore proper function |
What Are Vectors?
A vector is a delivery system used to carry the gene into target cells. Common vectors include modified viruses, which can enter cells but do not cause disease.
Real-Life Applications
| Disease | Type of Therapy |
|---|---|
| SCID | First successful gene therapy case |
| Cystic Fibrosis | Trials to insert correct CFTR gene |
| Parkinson’s Disease | Research ongoing to restore brain cell function |
| Eye Disorders | Gene therapy restored vision (e.g. Leber’s congenital amaurosis) |
Advantages of Gene Therapy
Treats the root cause – not just symptoms
Long-lasting effect – may last a lifetime
Fewer drug side effects – reduces medication need
Can help rare or untreatable diseases
Challenges and Risks
Immune reaction to the vector
Incomplete success – not all cells may accept the gene
Very expensive – some therapies cost over ₹1 crore
Wrong gene placement may cause side effects
Types of Gene Therapy
| Type | Description |
|---|---|
| Somatic | Targets body cells only – not passed to offspring (currently allowed) |
| Germline | Changes reproductive cells – passed to future generations (banned in many countries) |
Gene Therapy in India
India is in early stages of gene therapy development. Institutions like CSIR and AIIMS are conducting research, mainly on rare genetic disorders and cancer immunotherapy. Regulatory approval is overseen by ICMR and DBT.
Gene therapy offers a powerful way to fix diseases at the genetic level. It brings new hope for patients with inherited disorders, but also raises safety, ethical, and affordability concerns. As science advances, gene therapy could transform modern medicine – one gene at a time.
Pharmacogenomics
Pharmacogenomics is the study of how a person’s genes affect their response to medicines.
It combines pharmacology (study of drugs) and genomics (study of genes) to create personalized treatments.
Instead of giving the same dose to everyone, doctors can choose the right medicine and dosage based on your DNA.
Why Is It Important?
People respond differently to the same drug. One person might recover quickly, while another may experience side effects.
Your genetic makeup controls how your body processes drugs – including:
- How fast or slow a drug is broken down
- Whether the drug is effective or harmful for you
Real-Life Applications
| Area | Example |
|---|---|
| Painkillers | Some genes slow drug breakdown → risk of overdose |
| Cancer therapy | Tamoxifen works only if activated by a specific gene |
| Blood thinners | Warfarin dosage must match genetic sensitivity |
| Mental health | Effectiveness of antidepressants varies with gene variants |
Benefits of Pharmacogenomics
Right drug, first time – avoids trial-and-error
Fewer side effects – safer treatment
Accurate dosage – based on individual genes
Enables personalized, gene-based healthcare
Challenges and Concerns
High cost of genetic testing
Limited availability in many regions
Privacy concerns over stored DNA data
Unequal access in rural or low-income areas
Key Genes Involved
| Gene | Role in Drug Response |
|---|---|
| CYP2D6 | Breaks down many painkillers, antidepressants, and heart medicines |
| TPMT | Affects metabolism of immune-suppressing drugs |
| VKORC1 | Influences response to the blood thinner warfarin |
| HER2 | Guides targeted treatment for some breast cancers |
Pharmacogenomics in India
- Pharmacogenomics is currently used mainly in cancer care, heart disease, and psychiatry in India.
- Top hospitals and research centers like CSIR, ICMR, and AIIMS are expanding access to DNA-based prescriptions. Wider awareness, affordability, and public engagement are needed to scale its impact.
Summary:
Pharmacogenomics is transforming healthcare by making it more personal and precise.
It helps doctors choose the right medicine at the right dose for each individual – based on their genes. As research expands, this field holds the key to safer, faster, and more effective treatments.