Question

Why was it difficult to use dna as evidence in a crime before pcr was invented?

Answer 1

This should have the answer to your question. :) I found it on bitesizebio.com

Answer 2

Because the amount of DNA found on a crime scene was very little.

Step-by-step explanation:

PCR is the acronym of polymerase chain reaction. It is a method to make many copies of a specific DNA segment. By using this method the DNA sequences are exponentially amplified. Because of that, the little evidence found in a crime scene that before was useless, with this technique it became crucial to the criminal forensics.

I hope this answer helps you.