Hi

I was stuck while trying to get the top genes that had the highest expression variance across patients. I have a gene expression data and I would like to choose only lets say top 200 genes that had the highest expression variance across patients.

How do i do this in R?

I tried x=apply(leukemiadata,1,var)

x1=x[order(-1*x)]

**leukemiadata, is suppose my data with all the expression values

but the problem here is x and x1 are numeric data , If I choose the first 200 after sorting in descending, so I do not know how to choose the associated samples with just the numeric values.

Kindly help!