Single sample, more than one SRA file

[Gonza]

Hello All,

I want to download some samples from the SRA (http://www.ncbi.nlm.nih.gov/geo/quer...i?acc=GSE22411) but sometimes a single sample has more than one SRA file, which is a bit confusing.

For example, I want to download one sample (GSM567808 - 2C wild-type from above link) and when i click on it there are 3 SRA associated with it (SRR094075, SRR094076,SRR094077). They are not heavy at all (MB) so I am not sure why there are different SRA accession associated with one sample. Do i download the 3 SRA and merge the files?

Link for GSM567808 sample:

http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSM567808

Click on Download (ftp) and get the SRA as seen in:

ftp://ftp-trace.ncbi.nlm.nih.gov/sra...X038/SRX038411

Thanks very much
G

[Richard Finney]

This ~might~ be it ...

From the paper ( http://www.nature.com/nature/journal...ture09290.html
) ... "Regulation of heterochromatic DNA replication by histone H3 lysine 27 methyltransferases" ...

"thirty nuclei of each ploidy level from three biological replicates were analysed."

So it's probably just replicates of same sample.

[Gonza]

Thanks Richard.
I had seen that, but it is still confusing. In my experience, when you submit biological replicates to GEO each biorep gets its own SRA. Should I analyze these as bioreplciates?

Thanks again for your help!

Best
G