Cold Spring Harbor Labs on Long Island is primarily about research, only secondarily about grad students. Most of these people are post-docs, selected from a worldwide pool of applicants without nationality restrictions; getting in for a few years is quite competitive. The non-US are under-represented because of all the highly qualified ones who fail to get visa and work permits. The US citizens are underrepresented because the culture of US high schools, thanks to local control by school boards, undervalues science and other hard work.
