1. Mutations
What you need to know

2. DNA
DNA

3. Definition of Mutation
A random change in an organism’s DNA
Can be inherited – passed down from a parent to their offspring
Can be caused by mutagens – mutation causing agents in the environment
Some mutagens are carcinogens

4. Mutation = a random change in an organism’s DNA

5. Some mutations occur with large parts of the chromosome
Chromosomes have a long arm and a short arm.

6. Deletion – Removal of part of one arm of a chromosome
Inversion – Part of a chromosome arm is flipped
Duplication – Part of a chromosome arm is included twice
Ex: A deletion on the short arm of Chromosome #1….This means part of chromosome #1 is missing from the short side.

7. Chromosome 14 has a mutation (Possibly a deletion?)

8. Trisomies and Monosomies
One chromosome pair either has three (Trisomy) or only one (Monosomy) chromosome
Trisomy 21 (Down’s Syndrome)
Turner’s Syndrome – Monosomy in Sex Chromosomes

9. Some Mutations occur within a particular gene

10. Result of a Mutation?
The job of DNA is to hold a code that tells your body to make a certain protein. These may be pigments (coloring), enzymes (help chemical reactions in your body happen), or other proteins
If your DNA has a mutation in a gene, your body may not correctly make that protein. This can cause no problems, small problems, or very big problems for your body.
A mutation in a big part of a chromosome will cause a syndrome – a group of associated disorders

11. What Can Mutations Do?

12. Mutations can be POSITIVE (helpful)
Some mutations can provide an advantage which helps the organism survive
This give the organism an advantage in survival – and plays a part in the evolution of a species.

13. (not harmful, not helpful)
Mutations can be NEUTRAL
(not harmful, not helpful)
Some mutations do not effect the organism’s survival (the mutation does not help or hurt the organism)
bright green feather mutation
syndactyly
Normal (dark green feathers)

14. Mutations can be NEGATIVE (harmful)
Some mutations are harmful, and hurt the organism’s chances for survival
Again, this plays a part in the evolution of a species.
Mutated blood cell (person with sickle cell anemia)
Normal red blood cell

15. Some mutations can be helpful
Some mutations can have no effect
(NEUTRAL)
Some mutations can be harmful

16. Whether a mutation is POSITIVE, or NEUTRAL, or NEGATIVE may depend on the environment
Ex: Which bird would have the best chances of survival in a forest where all the leaves were BLUE?
People who are carriers of the sickle cell trait (Ss) are slightly resistant to malaria.