Data Retention Regulations in the Lords

[Roland Perry]

In article 
<889e91640903300940m4cc3b52djbef50672aceef6c4@mail.gmail.com>, Alan 
Braggins <alan.braggins@gmail.com> writes
>>> While DNA itself is a blueprint of a single individual and, of course, 1%
>>> of the population has a genetic twin,
>>
>> Would it help if the people who have such twins are marked in the database?
>> Then 99% of the queries could say "ah - this is likely to be a unique
>> fingerprint" while the other 1% will say "hang on a minute, we have two
>> people this might be - was it 2 year old or a 50 year old that robbed the
>> bank?"
>
>Twins are generally the same age.
>http://en.wikipedia.org/wiki/Twins#Statistics says 1.9% though, not 1%.

(Although only 0.2% are identical twins)

If we are talking about such identical twins, then that's a completely 
different issue. If you arrest the wrong one, he can always finger his 
sibling (modulo a few corner cases with adopted twins who don't know 
they are a twin).

I thought the expression "genetic twin" above meant two unrelated people 
who just happened to have the same 'fingerprint'.

>(As for marking people who aren't twins but have duplicate results for
>the subset of DNA tested, that only helps if all of them have been
>tested and put in the database.)

You'll only get potentially false positives if both are in the database.
-- 
Roland Perry