[Seg B]

Seg B  asked the Naked Scientists:
   
How much computer memory would a persons genome take up?

Segen, London

What do you think?

[Geezer]

My thinking:

The haploid human genome occupies a total of just over 3 billion DNA base pairs.

Human genome (Wikipedia)

DNA consists of combinations of 4 different base pairs that are able to be encoded as 2 binary bits (ie, 4 = 2², where the base of 2 indicates "binary" and the power of ² indicates number of bits). Thus,

3,000,000,000 base pairs → 1,500 Mega bits

1,500 Mega bits ≈ 100 MB of 16-bit words, 50 MB of 32-bit words, and 25 MB of 64-bit words.

Dave: I think 3 billion base pairs will need at least 6 billion bits, or approximately 750 Mega Bytes (8 bit Bytes)

In practice, depending on the actual encoding method, including some structure and a certain amount amount of redundancy, 1 GB is probably a practical minimum. I would not be surprised if actual genome files are considerably larger. Still, these days, a few GB is not much, and you could easily carry around your own sequence on a flash card!

[Bengaman]

Wow that's quite cool, can pick up 1GB cards for dirt cheap these days!

[Geezer]

If you can find one that small! I bought a 4GB keychain USB for my wife today for $15.