How does GC content affect DNA storage stability and readability?

• A. Very high or very low GC content can hinder synthesis/read accuracy; balanced GC improves stability and sequencing performance.
• B. GC content has no effect on stability.
• C. Only high GC is favorable.
• D. Only low GC is favorable.

Answer: (D)

GC content sets how tightly DNA strands hold together, which directly influences both storage stability and how easily the sequence can be read. If GC content is very high, regions become very stable and hard to denature, making synthesis, amplification, and sequencing more error-prone or incomplete. If GC content is very low, regions can melt too easily and primer binding or read consistency can suffer, leading to unreliable data. A balanced GC content hits a sweet spot: it provides enough stability for reliable storage without creating regions that stubbornly resist denaturation or cause sequencing biases. That’s why stable, readable DNA tends to come from sequences with a moderate, balanced GC content.