Usage of genetic information
Do you remember what alleles are in I/GCSE Biology?
- Different forms of the same gene are called ALLELES.
- You inherit one allele for each gene from your father and one allele for each gene from your mother.
- For example, the gene for eye colour has alleles for blue eye colour and alleles for brown eye colour.
- Your eye colour will depend on the combination of alleles you have inherited from your parents.
- Some diseases are inherited from our parents though our genes: they are called GENETIC DISORDERS.
- They occur because of faulty or defective alleles.
- Cystic fibrosis is caused by a recessive allele. You need to inherit two copies of the faulty allele to be born with cystic fibrosis. If you have just one copy, you are a CARRIER
Cystic fibrosis affects the cell membranes causing a THICK MUCUS to be produced in the lungs, gut and pancreas.
- Thick and sticky mucus
- Breathing problems
- Chest infections
- Difficulty digesting food
HUNTINGTON’S DISEASE is another genetic that affects the central nervous system.
- However is caused by a dominant allele – the presence of just one dominant allele can cause the disease.
- You only need to inherit one copy of the faulty allele to have Huntington’s disorder, unlike cystic fibrosis, where you need to inherit both copies.
- You can inherit the disorder if one or both of your parents carry the faulty allele, because it is DOMINANT.
- Uncontrollable shaking
- Memory Loss
- Inability to concentrate
- Mood changes
And we're done with this topic! Well Done!
- "Genetic diseases", https://www.mayoclinic.org/-/media/kcms/gbs/patient-consumer/images/2013/11/19/10/05/ds00549-autosomal-dominant-inheritance-pattern.jpg
- "Cystic fibrosis". Photo from the internet.
- "Cystic fibrosis", https://upload.wikimedia.org/wikipedia/commons/9/9a/Cysticfibrosis01.jpg
- "HUNTINGTON’S DISEASE". Photo from the internet.
- "Huntington's Disease", https://i.ytimg.com/vi/M6Z9bkd7zF8/mqdefault.jpg