Journal of Medical Genetics (1974). 11, 335. Absence of the a-thalassaemia syndromes in Egyptian Arabs

Summary. An investigation was undertaken to find the incidence of a-thalas-saemia in Egypt. Blood was collected from the umbilical cords of 550 newborns and from 630 adults from central hospitals in Cairo that drain patients from all over Egypt. Starch gel electrophoreses at both pH 8-6 and 7.0, and brilliant cresyl blue incuba-tion revealed the absence of haemoglobins Barts and H in the blood specimens examined. While much is known on the genetic, clinical, and chemical variations of the 3-thalassaemias and their combinations with other haemoglobinopathies, cor-responding information on the a-thalassaemias is at best fragmentary and unclear. It is now an accepted fact that haemoglobins Barts and H result from a reduction of a-chain syn-thesis, leading to an excess of either y or f8 chains, and hence to the formation of y4 and g4 molecules, respectively. The incidence of Hb Barts in cord blood is generally believed to be a reliable index of the pre-valance of ac-thalassaemias in a population (Weather-all, 1963). The frequency of Hb Barts in some ethnic groups of the old world has been reported and varies widely between them (Weatherall an