Looking at a company's short interest should be an integral part of an investor's due diligence. A high short interest isn't necessarily a reason shun a company, but understanding why investors are shorting the stock is important. The shorts may be wrong, but investors should be able to convince themselves of that before hitting the buy button.

In the following slideshow, you'll find info on the five most shorted biotechs on the Nasdaq -- Myraid Genetics (NASDAQ:MYGN), Sarepta Therapeutics (NASDAQ:SRPT), Questcor Pharmaceuticals (NASDAQ: QCOR), Ziopharm Oncology (NASDAQ:ZIOP), and MannKind (NASDAQ:MNKD) -- and a brief explanation on why each company is hated so much.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.