Further news on this:
The proposal is that although the DNA profiles will not be stored in the central database, they will remain at individual forensic facilities. It is currently unclear whether this is an attempted workaround of the European Court of Human Rights 2008 ruling (which ruled that the current Government scheme broke the European Convention on Human Rights), or a sincere aspect of practicality (the Government claims that these profiles are stored in mixed batches, with a batch containing both innocent and convicted persons' DNA, thereby making deletion difficult and, they claim, impractical).
There are, however, some serious concerns that the DNA of large numbers of innocent people will potentially remain available to the State and it's agents.