Dr. Lynn Hillyer:

That is a good question. The record is there in quadruplicate. The records are there from when the sample is taken right through to laboratory analysis. That is the chain of custody, which is very important. Accredited laboratories have checks and balances in place to ensure that processes are followed when samples are logged in. The samples are anonymised and have numbers assigned to them. The numbers are tracked through the laboratory.

DNA analysis has previously been requested. We can carry out DNA analysis of a sample if needed. It is not routine and is not usually needed because sufficient checks and balances are already in place.