I got a PhD genetics admit in both colleges, whats the best if i specialise in Human Genetics research?
That is a very tough question. I don't know anything specific about either of those programs, so I can't vote. I did recently finish my PhD so I do have some advice. Identify some PIs at those Universities whose work really excites you. Look at the overall quality of the publications from each department. Try and make personal contact with grad students in those departments, to see if they are happy. Also, consider location and quality of life. The midWest (Iowa) vs the South (clemson) are two very different places. Remember, you have to spend the next 6 years at this place, you don't want to hate it. Visit both schools if you can.
Good luck and enjoy graduate school.