Couldn't see a thread on it yet and am starting to watch Ep 1.
Looks like DNA profiling has improved dramatically and old cases that had samples taken are now being re-tested and entered into the databases. Police are now calling victims to re-open cases and catch offenders.
It did make me wonder why the DNA database isn't always running these / why they aren't entered into it to match when new DNA comes in? I am not a software company but surely no requests are needed for an offence, and if a relative is arrested they have to give DNA anyway, so if there was a link and someone's dad (for eg) had committed a murder or rape where DNA had been put into the system, it should recognise the similarities?
Anyway, it's a great series. Hopefully making some offenders sweat anyway!