Why did I get different probe IDs from that of the series matrix?

Question

[Chan]

Hi,

I intend to repeat data processing of a Genechip data set (accession number GSE51257). I used package 'affy' (version 1.64.0) to read the raw data and used rma to normalize data. The cdf file I used is from package 'hugene10stv1cdf' (version 2.18.0).

However my ids in expression matrix are from 7892501 to 8180418 (32321 rows) instead of the range from 7896736 to 8180719 (28832 rows). Anyone knows why this happened? If it's the problem of the cdf file, how can I find the same cdf as that used before?

Thanks in advance.

Chan