Mutations

• types of mutations

  • deletion
  • substitution
• The effect of a mutation depends on where it is in the DNA sequence
• deletion mutations have a massive impact if they're at the start of a DNA sequence as all codons downstream are effected by frameshift
• deletion mutations have the least effect when they are at the end of a sequence
• deletion mutations have a massive effect is they impact the stop codon
• substitution mutations have differing significance depending on where and which amino acid is changed
• substitution- one base has been changed, which could change the amino acid it codes for
• deletion- one base is deleted
• deletion causes a frameshift along the rest of the DNA sequence, changes every codon downstream of the mutation
• less codons downstream= less will be changed
• Non-disjunction is the failure of homologous chromosomes to separate during meiosis
• non-disjunction changes the number of individual chromosomes
• non-disjunction produces gametes with more or less than 1 chromosomes
• non-disjunction causes chromosomal disorders like down's syndrome