Sleep Apnea Treatment

A bit about myself:
I am going into a research/medicine related field of bioinformatics, so it will be easy for me to switch into biomed/biochem/etc if I need a different undergrad degree.
I’m not sure if I would rather be a sleep “scientist” or a “doctor”, but they are both as equally attractive to me. I would like to study how sleep works on the microscopic level, and possible develop drugs for treating (neurological) sleep disorders.
I am fascinated by dreaming and consciousness studies, and would like to study how (and why) dreaming and consciousness occurs.
Also, I would like to know if an undergrad degree in Bioinformatics would be acceptable for graduate studies in neuroscience/med school? If not, what routes would I have to take?
Thanks.

Has the technology changed or has there been new medical breakthroughs that would permit a sibling who was initially tested negative for compatibility for bone marrow 13 years ago, be able to test positive today in 2008 and provide such bone marrow?
Also, if the sibling has already tested negative and he/she decides to redo the test than mathematically speaking shouldn’t the test yeild the same result (i.e.: test negative)?
Moreover, if someone has sleep apnea, notably obstructive sleep apnea (OSA) in its severest form, and he/she wishes to donate his/her bone marrow (providing that the blood test is positive), how would this person be anaesthetised? Does this person need a sleep apnea machine, hence CPAP, attached to them during surgery? Is a surgeon able to perform surgery on this person? If so, how would he/she go about it given the sensitivity and gravity of this situation?
If someone has DVT, blood clotting and takes cumadin for life, can this person be tested ?

I am not even completely sure this is the proper title…
However, I would like to know the proper titles for people who study sleep disorders, including Doctors and I would like to know what sort of requirements are nec. for that.
Thanks!