Mutations and Gene Regulation

​Question?

What could go wrong with DNA replication or transcription?​

Transcription and Translation

• Transcription- inside the nucleus mRNA copies a gene that codes for a protein

• Translation- in the ribosome the mRNA is translated (using tRNA) into amino acid chain

• the polypeptide chain folds creating a protein

Gene regulation and mutation

​Mutation – change in DNA sequence

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Mutations can be induced by a multitude of environmental factors

• Radiation

• Chemicals

• Infectious Diseases​

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Multiple Choice

In genetic …………………is an alteration in the nucleotide sequence of the genome

• Mutation

• Segregation

• Both

• None

​Mutation Deletion

Deletion mutation – one or more nucleotides is removed from a DNA sequence​

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Deletion mutations cause frameshift (the entire amino acid sequence is altered past the deletion)

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**count the #of nucleotides*​

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​Mutation Insertion

Insertion mutation – one or more nucleotides is added to a DNA sequence​

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Insertion mutations cause frameshift also (the entire amino acid sequence is altered past the deletion)

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**count the #of nucleotides*​

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​Mutation ISubstitution

Substitution mutation – one or more nucleotides is substituted for different nucleotides in a DNA sequence​

Do not cause frameshift

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Silent mutations: the mutation does not affect the sequence of amino acids

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​Details

Write an example of the 3 types of gene mutations

1. Deletion

2. Insertion

3. Substitution​

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Multiple Choice

The model shows a mutation to a partial sequence of bases in a gene. Which type of mutation does the model demonstrate?

• DELETION

• INSERTION

• SUBSTITUTION

• TRANSLOCATION

Chromosomal mutation

​Chromosomal Mutations- a large scale change

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in a specific section of the DNA 🡪

causes a protein to malfunction

causes a different protein to be made

​Details

Gene mutation vs. Chromosomal mutation ​

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small, like the single change in a nucleotide/nitrogen base

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large, like an entire chromosome

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​Mutation afffects

​Disadvantages

• Diseases (Sickle Cell)

• Cancer

• Disabilities (Down Syndrome)

Advantageous

• Super taster (TAS2R38)

• ​Unbreakable bones (LRP5)

Neutral

• have no impact​

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​Summarize Mutations