Mutation

• Mutation

  change in genetic code/DNA
• Substitution

  Swap 1 base with another base
• silent substitution

  base substitution that results in no change of eh amino acids
• missense substitution

  results in the replacement of one amino acid for another in the protein made by the gene. the resulting protein will have altered in structures and function
• nonsense substitution

  results in a shortened polypeptide that may not function properly due to an early stop codon
• insertion

  adding a base
• frameshift insertion

  shifts the group of codons that code for 1 amino acid

  resulting protein is usually disfunctional
• deletion

  a base is removed
• what happens if mutation occurs in a germ-line cell(egg or sperm)

  Mutation can be passed on to offspring
• somatic mutations

  occur in cells elsewhere in an organisms body. these mutations are passed to daughter cells during mitosis but not passed to offspring

  effect: tumour or cells die
• spontaneous mutation

  arises naturally and not as a result of exposure to mutagens

  occurs due to errors in DNA replication
• causes of mutation

  physical: radiation

  Chemial: exposure to chemicals

  biological: viruses