Oh my Neelu, don't know where to begin....Can't speak for Qatar, but American studies have shown that East Asians-men in particular-are less willing to marry outside their ethnic group than Caucasians.  East Asian women are more willing than either black or Latina, while Caucasian men are the least discriminating about marrying outside their own ethnic group.  Maybe part of the reason this pairing is so apparent to you is because these are the two groups who are most willing to couple outside of their own ethnicity?  Now this study only applied to Americans of East Asian descent, so presumably their cultural perspectives would be different to those born and brought up there.