Mutations

1. Mutation—mistake in the DNA that causes errors in protein production. Mutations

2. Point mutation—mistake at a single point in the DNA. *insertion—extra base(s) *deletion—lacking base(s) *substitution—different base(s)

3. Point mutation con’t Insertion Should be: AAT TAG CCA GCG But is : AAT ATA GCC AGC G An extra base has been inserted where it should not be, causing a frameshift mutation. What amino acids are formed?

5. Deletion Point mutation con’t Should be: ATA TTA TAG CGA But is: ATT TAT AGC GA The A from the original strand of DNA is missing causing a frameshift mutation. What amino acids are formed?

6. Substitution Point mutation con’t Should be: ACC GTA CTA ATT But is : ACC CTA CTA ATT The C has substituted Where there should be a G. What amino acids are formed?

7. Chromosomal Mutations • Deletion—part of a chrosome is missing. • Duplication—creates extra copies of parts of chromomosomes. • Inversion—reverse the direction of parts of the chrosomomes. • Translocation—part of one chrobreaksmosome off and attaches to another.

8. Significance of Mutations • Most are neutral (no problem, no benefit) • Some can cause dramatic effect on proteins created (big problem) (Can I use baby powder instead of flour for my cake?) • But some may be very beneficial, and provide a source for genetic variability (I substituted chocolate for nuts, and this cake is the best I’ve ever had!)