Question

Which one of the following vector types is suitable to clone \(2000\) kb DNA insert?

• A. Bacterial plasmid
• B. Bacteriophage
• C. Cosmid
• D. Yeast artificial chromosome

Hint:

YACs are used for cloning extremely large DNA fragments, while plasmids, phages, and cosmids are suitable only for smaller inserts.

Answer 1

The Correct Option is D

Step 1: Read the size needed.
We must hold a huge insert of $2000$ kb. So we need a vector with a very large carrying limit.

Step 2: Recall capacities.
Plasmids take only about $10$ kb. Phage lambda manages around $20$ kb. Cosmids reach maybe $45$ kb. All of these fall far short of $2000$ kb.

Step 3: Pick the big carrier.
Yeast artificial chromosomes are built to behave like real chromosomes and can hold hundreds to thousands of kb, easily fitting a $2000$ kb piece.

Step 4: Answer.
So the right vector is the yeast artificial chromosome. \[ \boxed{\text{Yeast artificial chromosome}} \]