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Mutations!. Types of Mutations . Point Mutations: one base is changed Substitutions Insertions Deletions Both Insertions and Deletions are also called frameshift mutations because the codons are not read correctly Mutations can happen in both DNA and in RNA. Mutations.
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Types of Mutations • Point Mutations: one base is changed • Substitutions • Insertions • Deletions • Both Insertions and Deletions are also called frameshift mutations because the codons are not read correctly • Mutations can happen in both DNA and in RNA
Mutations mRNA AUU GCC GCG AAG GCU AUC UUA Isoluecine Alanine Alanine Lysine Alanine Isoluecine Stop Frameshift Mutation (Insertion) AAU UGC CGC GUA GGC UAU CUU A Asparganine Cysteine Arginine Valine Glycine Tyrosine Leucine Point Mutation mRNA AUU GCC GCG AAG GCU AUC UUA Isoluecine Alanine Alanine Lysine Alanine Isoluecine Stop AUU GCC CCG AAG GCU AUC UUA Isoluecine Alanine Proline Lysine Alanine Isoluecine Stop
Types of Mutations • Chromosome: DNA condenses into 46 chromosomes (23 pairs) • Inversions– when part of a chromosome breaks off, turns around and reattaches in the reverse order • Translocation – a chromosome part breaks off and attaches to a different chromosome TAG GCC CAG CTG TCA CAG TAG GCC CAG CTG TGA CAG
Not Harmful? • Mutations will not a have negative impact on the phenotype in the following cases: • If they occur in an intron section of the DNA • If they still code for the same amino acid • Ex. UAU and UAC both code for Tyrosine
Cancer • Cancer when a cell begins to divide uncontrollably. • Benign: stays contained, does not harm surrounding tissues • Malignant: cancer cells can invade and damage surrounding tissues and organs or spread to other places in the body • Some cancers can be inherited from our genes while others form after birth during the DNA replication/copying process (mitosis)
Cancer • Factors in the environment cause mutations are called “mutagens” (ex: UV Radiation, many chemicals, etc.) • Mutagens that cause cancer are called “carcinogens” (ex: tars in smoke, some drugs, some viruses, UV Radiation (sunlight), etc.)