Topic 8

Question 1

DNA variation and sequencing

Answer 1

Both common polymorphism and rare mutation as a result of changes in DNA

Question 2

Typed DNA variation and sequencing

Answer 2

1. SNPs: ( single nucleotide polymorphism)
2. Indeed ( insertion - deletion)
   - Nonrepetitive
   - STRs (short tandem repeats)

Question 3

SNPs

Answer 3

• most common type of genetic variation among humans
• single base pair differences between DNA sequences

Types
1. Transition : replaces pyrimidine with pyrimidine or purine to purine ex : AT—> TA
2. Transversion : replaces a purine to pyrimidine or vice versa ex: TA—> CG

Question 4

Causes of SNPs

Answer 4

1. Spontaneous DNA replication error( mismatch)
2. Other chemical changes to nucleotides( occur naturally in cell eg: repudiation, deamination
3. Induce mutations
   - exposed to chemical mutagens
   
   • can replace a base or alter mutagen/ damage a base