Will Big Data DNA analysis herald new era in medicine?

Often, you are barely aware of it, but hop on a train, spend some time in the shops, watch a movie or a match or visit your GP, and the chances are you will have contributed to half a dozen collections of mass data.

In the past this data was left unused, but with computer hardware changes bringing improvements in speed and power it is becoming possible to gather and analyse that information on a grand scale - this is Big Data.

Now the UK government has Big Data plans for perhaps our most intimate information - our DNA - the genetic code that describes us. So, will it herald a new era in medicine, and who will decide who gets to know what? Newsnight's Susan Watts reports.