2. Mutations Learning Goal: Identify mutations in DNA (point mutation and frameshift mutation caused by insertion or deletion) and explain how they can affect the expression of genetic information.

3. The types of proteins an organism possesses depend upon the sequence of nucleotides

4. The two main types of gene mutations include: – Point mutation: one base pair is replaced for another base pair. – Frame shift mutation: one or more base pairs are added or deleted.

5. -A point mutation can cause an amino acid to change, which will change the structure of the protein being made. Example: AUG=Met AAG=Lys -Only one letter was changed (the A to a U) and the entire amino acid changed (from methionine to lysine). Point Mutations

6. Frameshift Mutation A nucleotide (or nucleotides) are added to a gene sequence. Insertion A nucleotide (or nucleotides) are subtracted from a gene sequence. Deletion Insertion Normal = ATCGCGCCCACT Mutated = ATCGGCGCCCACT Deletion Normal = ATCGCGCCCACT Mutated = ATCGCCCCACT

7. Result More than one codon can be altered, thus frameshift mutations tend to result in greater changes to the amino acid sequence and to the structure of the protein.

8. The types of proteins an organism possesses depend upon the sequence of nucleotides

9. THE DOG BIT THE CAT THE DOG BIT THE CAR Point or frameshift?

10. THE DOG BIT THE CAT THE DOB ITT HEC AT Point or frameshift?

11. Sickle Cell Anemia -People with sickle cell anemia often experience a lot of pain and swelling and have trouble exercising.

12. Sickle Cell Anemia Problem: a point mutation in the gene that codes for hemoglobin, the protein that carries the oxygen. Normal hemoglobin makes normal red blood cells. Mutated hemoglobin changes the shape of the cells. Sickled red blood cells get stuck in narrow blood vessels, damaging organs. It can be fatal. 1 amino acid out of 237 is different!!

13. What kind of mutation is this? Original Mutated

14. Exons and Introns Some RNA must be removed! Some RNA does not code for proteins! Interons – removed! They interupt Exons – express genes!

15. In eukaryotes, the new RNA molecule is actually called pre-m RNA. It contains large segments of DNA that do not code for any proteins. These non-coding segments of DNA are called introns These introns are spliced out and the remaining segments of RNA are cut and pasted together. The segments of DNA that code for proteins are called exons.

16. Splicing! Eukaryotes have spliceosomes Spliceosomes are responsible for splicing introns out They can pick and choose what will be an intron or exon = alternative splicing!

17. mRNA Splicing Occurs after Transcription Introns are removed and exons are spliced together to make the mature mRNA transcript eukaryotic DNA exon = coding (expressed) sequence intron = noncoding (inbetween) sequence primary mRNA transcript mature mRNA transcript pre-mRNA spliced mRNA ~10,000 bases ~1,000 bases

18. Translation: (Protein Synthesis)=decoding of m-RNA into amino acids to form proteins