Pedigree Query

I just got my this month's Smithsonian, and it has a long article about microRNA. From what they say, it's a form of gene that does not produce proteins, but short circuits protein production. There are supposed to be thousands of them.

So now we have "junk" on the Chromosome strands that does things we don't understand yet; and we have these new micro genes that affect the macro genes.

Anyone got more insight into how microRNA might work in the horse?