Once you start at any US med school, and they know that, they will be very unlikely to accept you if they know you are already attending somewhere else. Did you not apply to MD this year? If you only want an MD, it might be better for you in the long run to just hold off attending the DO school and reapplying MD, especially if that is your plan to begin with. Good luck.
Edit: I also wanted to add that it would be significantly cheaper to just rewrite the boards after getting your DO, rather than paying for an extra year of med school. The costs of this would be very discouraging if nothing else was...
Therefore, I am considering of applying to US MD schools in this cycle . But my QUESTION is: Where they ask you in the applicaton whether I am currently enrolled in medical school, will answering yes diminish my chances of getting an interview?
Uh, yes, it is likely problematic. You see, you are already a medical student, someone who has matriculated and is currently enrolled in a medical school in the US. This effectively prevents you from applying elsewhere in the US...
I would talk to some adcoms at allopathic medical schools and see what they say. See if you can make them understand your plight. However, it is likely that you are going to be faced with some serious challenges in your task. I doubt it would be likely for you to get accepted elsewhere.
I don't want to say that you can try to transfer between schools, because that's pretty unlikely as well.
Honestly, I think you would be better off simply finishing your education where you are and just take two boards. I'm no expert, however. Try asking in the advisor forum here on SDN, where there are verified adcoms, who can better address your question.