Define foreign? Does the Middle East count, what about Afghanistan?
Pakistan has a long exhausting history of foreign invasions. The Mongols no doubt had the biggest impact, not necessarily racial though. South Asia is quite diverse in terms of y-dna haplotypes, R1a is prevalent in most Pakistan and some India. J2 which belongs to the semitic people of the Middle East is surprisingly non existent in Pakistan. Yet half of them claim to be of Arab descent. South Asia as a whole reflects a wide range of haplotypes.