I don't have a degree and it doesn't seem to hurt me in job searches at this point, now that I have ~4 years of professional experience. However, I've spent a lot of time learning about and reading books on CS topics, including quite "academic" stuff like programming language semantics and type theory, so maybe I'm not typical of self-taught programmers. Not having a degree made it much more difficult starting out, but I got in "through the back door" by getting a non-programming job at a company which gradually gave me more programming responsibilities as they realized I could do it.
I wonder if there's some way to combine your biology study with software development? I've found that in jobs that are about applying technology to some other domain of business or endeavor - which is just about all of them - (mis)communication between the business/domain experts and the technical experts is usually the biggest bottleneck, and it helps a LOT to have people who understand both. Plus, it seems like it would just be more interesting than generic business programming jobs, and probably more of a growth area in the next couple decades.