I don't know. I do know that RNA is a lot more fragile than DNA. RNAses are everywhere. I did maybe 1 or 2 Northern blots (RNA for the layman) in my life and you had to be very meticulous in handling them.
info for layman: Southern (named after the scientist that developed it) blots are DNA run in a gel to sort by size, blotted onto a membrane and then probed with a radioactive fragment. Northerns are the same with RNA and Westerns are with proteins.