Lecture 4

Question 1

What is the usual primer length

Answer 1

18-30 bp for specificity

Question 2

What r good primer characteristics

Answer 2

• close match 2 site
• Even base content
• G or C at 3’ end (stronger bond)
• similar melt temp 4 the pair
• no dimers

Question 3

What are ways to prevent dimers?

Answer 3

• Using a higher annealing tenmp at the beginning so that primers bind specifically at first
• Hot start DNA pol, means no primer binding before the dsDNA unravels completely

Question 4

For agarose gel, what concentration gives better resolution?

Answer 4

higher concentration. Range is abt 0.5 - 3%