How does insert size affect downstream bioinfo analysis?

[ymc]

This is extracted from a BGI doc:

http://bgiamericas.com/wp-content/up...-2012.8.22.pdf
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4. What insert size of FFPE samples and fresh frozen (FF) samples is used for library construction?

Based on our project experience, sizes are:
• DNA FFPE samples: about 100bp
• DNA FF samples: about 120bp
• RNA FFPE samples: about 150bp
• RNA FF samples: about 200bp
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Does knowing this affect downstream analysis? How do these numbers relate to fragment size?

Thanks in advance.