Similarly, a strong signal adjacent to the HBB cluster recently detected in African-American patients at rs5006884 in OR51B5/618 was not found to have significant association in either Tanzanian14 or Cameroonian SCD patients.13 These findings suggest that studies of multiple SCD populations in Africa are warranted to improve our understanding of the impact of human diversity on HbF expression in SCD.19 The gene discussed is HBB; the disease is Schnyder corneal dystrophy.