Hi, I have miRNA expression data. From what I read from the documents,

"The samples were labeled using the miRCURY LNA™ microRNA Hi-Power Labeling Kit, Hy3™/Hy5™ and hybridized on the miRCURY LNA™ microRNA Array (7th Gen) following a single-color experimental design."

I want to combine it with public data set GEO GSE15885 (http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE15885). According to their documentation, the samples were "Labelled RNA was hybridised to LNA™ miChip array platforms (Exiqon version 7, containing 453 miRNA sequences) "

Now I downloaded the GSE15885 data in R. The miRNA measured in this data are different from the data I have. For examples, miRNA : hsa-let-7a that exists in GSE15885 does not exist in my data set, however there is hsa-let-7a-2-3p.

My question is, how can I combine the two data sets? Also, the data set GEO GSE15885 also contains more than more reading for a single miRNA. For example, 'hsa-let-7d' is seen twice per sample in this data set. How would I tackle this during my DE analysis?