There are DOs on faculty at Temple, Jefferson, Penn, Drexel, and CHOP. There are DOs on faculty at Mayo, Cleveland Clinic, and even Yale-New Haven.
DOs in MD Academia are out there ... but you have to search for them. Will you find one at every place? No. And I would surmise that percentage wise, there are fewer DOs in MD Academia than the standard ratio of total DOs to total MDs. Several reasons for this conclusion:
1. Most DO schools are not located at major research centers where NIH grants come in boatloads. As a consequence, fewer exposure to clinicians who are purely academic/research focused and also fewer mentors.
2. A higher percentage of DOs go into primary care compare to their MD counterpart (less likely do go into academia/research)
3. Training at a major research university is important if you want to be on faculty at a major university. Not an absolute requirement but helps if you want to break into the world of academia.
4. Academia, while more prestigious, pays a whole lot less than private practice. A 2003 survey shows that an academic primary care physician makes around $131,926, compare to $153,231 for a private practice primary care physician. For academic specialists, it's $175,000 compare to $274,639 for private practice.
* Data from Medical Group Management Association Compensation and Production Survey. For private practice physician, earnings are gross revenue minus overhead. For academic physician, earnings are straight salary plus bonuses (where applicable). Benefits are not included in the data.
As a DO, can you go into academia. Yes. It's not prohibited. You'll be a rarer breed, but it's possible. And if you're located near a major DO school (CCOM, NYCOM, PCOM, UMNJD, etc) - it won't turn as many heads as you might think.
Also a word of caution to the original poster ... if you plan on going into academia, don't rush to generalization based on observation alone (e.g., I have yet to see a DO in academia, therefore there must not be any DOs in academia)