P53 tumor suppressor gene RAS protooncogene APC tumor suppressor gene Are

P53 tumor suppressor gene ras protooncogene apc tumor

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P53 tumor suppressor gene RAS protooncogene APC tumor suppressor gene Are mutations a good or bad thing for a species’ survival? Sometimes good and sometimes bad What gene is known as risk factor for women for breast and ovarian cancer? BRCA 1
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Bacteria are able to increase mutation rate in response to environmental stress TYPES OF MUTATIONS Point mutations : altering a single base pair or small group of adjacent base pairs Base substitution: one pair is replaced by another Insertion: One or more base pairs added to a DNA sequence Deletion: One or more base pairs removed from DNA sequence Synonymous : silent mutation, change codon for another codon for the same amino acid Missense : change codon for codon of a different amino acid Conservative : switch out one for another, where they are chemically similar, acts similarly to the old one, not much change in the shape of the polypeptide Non conservative : replace one amino acid with a chemically different one, different set of chemical reactivity, STRUCTURE IS FUNCTION, change the structure and function of the protein. More severely alter. Nonsense mutation: change amino acid to a Stop Codon. Have large effect on protein function. Insertion : one or more base pairs are added to the sequence Deletion : one or more base pairs are removed from the sequence Frameshift mutation: mutation that changes the reading frame. Can come from either an insertion or a deletion. Negative effect on the genes function. Can severely alter the amino acid sequence of a polypeptide. Mutations in non coding regions: Promoters Splice sides Ribosomal binding sites Transcription factor binding sites Krisper method: modify gene expression (used on tomatoes) can use it like a dial to change certain properties TATA box mutation can stop formation of protein Abnormal exon splicing , if splice sites are changed Some mutations may not have an effect on phenotype Synonymous subs Control of Gene Expression (chromatin to mRNA in eukaryotes) + mutations A mutation you can NOT pass onto your offspring would occur in the: somatic cells Most mutations that occur in our genomes are: neutral Which mutation would most likely have the least effect on the gene of interest? Synonymous Mutation When chromosomes get shorter its a: Deletion mutation
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Missense mutation: Results in the production of a different amino acid than intended Nonsense mutation: result in the production of a stop codon. This can afffect protein function Frameshift mutation:Changes the reading frame of the codon so different amino acids are coded for. Missense : change codon for codon of a different amino acid Conservative : switch out one for another, where they are chemically similar , acts similarly to the old one, not much change in the shape of the polypeptide Non-conservative: replace one amino acid with a chemically different one, different set of chemical reactivity, STRUCTURE IS FUNCTION, change the structure and function of the protein. More severely alter.
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