Inflammatory bowel disease and African Americans (Reply)

We thank Dr El-Tawil for his interest in our article. He quoted the extensive study of Mahid et al. (1), conclud- ing that in the USA there is no racial difference between African American populations and Caucasian American populations in inflammatory bowel disease (IBD) pre- sentations, as well as in incidence and prevalence of Crohn's disease (CD) and ulcerative colitis (UC). The hypothesis of Dr El-Tawil is that genetic alleles to IBD from Europeans have been transmitted to African Americans since their arrival as slaves in America in the 17th century.