Appraisal of sickle-cell and thalassaemia genes in Saudi Arabia.

A comprehensive national survey of the distribution of the sickle-cell (Hb S) gene and thalassaemia genes was initiated in 1982, with more than 30,055 blood samples collected. The Hb S, alpha- and beta-thalassaemia gene frequency range was 0.005-0.145, 0.01-0.40 and 0.01-0.15 respectively in various areas of Saudi Arabia. We present here an appraisal of sickle-cell and thalassaemia gene occurrence in the Saudi population, based on our studies conducted over 10 years in different regions of Saudi Arabia.