Welcome to Genetic Mutations! 7x2WSY 7x2WSY

Share out! Today’s objective: SWBAT explain how genetic mutations occur SWBAT distinguish between the 3 types of genetic mutations GENETIC DISORDERS ARE CAUSED BY GENETIC MUTATIONS!!!!!!

A. Introduction to Mutations -A mutation is a change in DNA sequence (order of nucleotides). -Mutations are important because they increase genetic variation.

Mutations in Body Cells -Mutations in body cells cannot be passed on to your children, however, they can cause cancer or other problems in your body. A cancer cell.

Cancer as a result of mutations in body cells: A person with skin cancer-This is why it’s important to always wear sunscreen!

Cancer as a result of mutations in body cells: Tongue cancer and lung cancer are often caused by changes in body cells as a result of smoking, so don’t smoke!!!

Mutations in Reproductive (Sex) Cells -Mutations in sex cells (sperm and egg cells) can lead to changes in the DNA sequence which can be passed down to a person’s children.

Mutations in sex cells -X-men and X-women would be a result of mutations in sex cells. These people inherited mutated (changed) DNA from their parents:

Good vs. Bad Mutations Mutations can be good as well as bad. A good mutation could lead to a change in a protein that allows an animal to run faster or see better. A bad mutation could lead to a change in a protein that causes a genetic disease such as Sickle Cell Anemia or Hemophilia.

TURN AND TALK WHAT IS A MUTATION? WHAT IS THE MAIN DIFFERENCE BETWEEN MUTATIONS IN SEX CELLS AND MUTATIONS IN BODY CELLS?

B. Gene Mutations There are 3 main types of gene mutations: 1. POINT MUTATIONS SUBSTITUTIONS 2. SILENT MUTATIONS 3. FRAMESHIFT MUTATIONS INSERTIONS DELETIONS

1. Point mutation -Point mutation-a change in one base pair in a DNA sequence. Example: AUG=Met AAG=Lys -A point mutation can cause an amino acid to change, which will change the structure of the protein being made.

POINT MUTATION

Picture of A Point Mutation Normal Point mutation mRNA Protein Stop mRNA Protein Replace G with A

Point mutations in our lives! -Sickle cell anemia is a blood disease caused by a point mutation. - A single nucleotide is changed from “A” to “T” which causes the amino acid to change from glutamic acid to valine: Normal: ACT CCT GAG GAG Amino Acids: Thr – Pro – Glu – Glu Sickle cell: ACT CCT GTG GAG Amino acids: Thr – Pro – Val – Glu

Point mutations in our lives! -People with sickle cell anemia often experience a lot of pain and swelling and have trouble exercising. Sickle cells do not move smoothly through blood vessels like normal cells do. Sickle cells get stuck and cause blood clots. Sickle cells also can’t carry Oxygen as effectively as normal Cells.

2. SILENT MUTATION A TYPE OF MUTATION THAT RESULTS IN A CHANGE IN CODON BUT DOES NOT CHANGE THE AMINO ACID CREATED.

Codons can code for the same Amino acid!

Silent Mutations Single nucleotide mutation that does not result in a change in the amino acid sequence of the protein made

THINK PAIR SHARE WHAT IS THE DIFFERENCE BETWEEN A POINT MUTATION AND A SILENT MUTATION?

-Frameshift mutation- Adding or deleting nucleotides to a DNA sequence. -A frameshift mutation is much worse than a point mutation because it causes the entire DNA sequence to be shifted over! Example: DNA: ATTAAACCG ATAAACCG 3. Frameshift mutation Delete this T

2 types of Frameshift mutations: INSERTIONDELETION

FRAME-SHIFT MUTATIONS: Insertion: Nucleotide added – Entire DNA sequence changed Deletion: Nucleotide missing – Entire DNA sequence changed

V. Frameshift mutation mRNA Protein Frameshift mutation Deletion of U

Frameshift Mutations Crohn’s Disease is caused by a frameshift mutation. It causes inflammation to the digestive tract.

THINK PAIR SHARE WHAT IS THE DIFFERENCE BETWEEN A POINT MUTATION AND A FRAMESHIFT MUTATION?

Difference between a point mutation and a frameshift mutation.

BRAIN POP VIDEO ynlk

GUIDED PRACTICE- WHITEBOARDS Is this a point mutation or a frameshift mutation? -It’s a point mutation because only one nucleotide changed!

Questions: THE DOG BIT THE CAT THE DOG BIT THE CAR Point or frameshift? Point!

Questions THE DOG BIT THE CAT THE DOB ITT HEC AT Point or frameshift? -frameshift

GUIDED PRACTICE WHAT IS THE NAME OF THE TYPE OF MUTATION THAT RESULTS IN A CHANGE IN CODON BUT DOES NOT CHANGE THE AMINO ACID?

SILENT MUTATION SILENT MUTATION A TYPE OF MUTATION THAT RESULTS IN A CHANGE IN CODON BUT DOES NOT CHANGE THE AMINO ACID CREATED.

GUIDED PRACTICE What type of frame-shift mutation is shown below?

Answer INSERTION- Frameshift

GUIDED PRACTICE What type of frame-shift mutation is shown below?

Answer DELETION- Frameshift

WHAT TYPE OF MUTATION IS SHOWN BELOW?

Answer POINT

BEFORE THE MUTATION, A DNA CODON CODES FOR THE AMINO ACID VALINE. AFTER THE MUTATION, THE DNA CODON STILL CODES FOR VALINE. WHAT TYPE OF MUTATION IS THIS?

Answer SILENT

Objective Today’s objective: SWBAT explain how genetic mutations occur SWBAT distinguish between the 3 types of genetic mutations Rate 1-5 on how confident you feel with these objectives 1- Poor 5- Excellent