FREQUENCY OF GLUCOSE-6-PHOSPHATE-DEHYDROGENASE DEFICIENCY IN RELATION TO ALTITUDE - A MALARIA HYPOTHESIS

Abstract

Genetic markers were recently found to be much more polymorphic than expected. Such extensive human polymorphisms may be partly explained by a number of genetic and environmental factors, including infectious diseases. Malaria, which still poses a problem in many countries today, needs research. The association between malaria and glucose-6-phosphate dehydrogenase (G6PD) deficiency is well-known, but more should be done to determine the mechanisms responsible for this positive correlation and to confirm that malaria is a strong selective factor for many other genotypes also. A WHO project on genetic markers and susceptibility to infectious diseases, which is concerned mainly with G6PD deficiency and the following genetic markers; hemoglobinopathies, including the .beta.-thalassemia trait and ABO, Rh, MN, Duffy, secretory types (Ss), and human leukocyte antigens (HLA), is reported. Since malaria was eradicated in Bulgaria many years ago, human populations from this country, living at different altitudes above sea level, were used as a model for analysis of the malaria hypothesis. The data for G6PD deficiency confirm that malaria was a selective factor in lowland areas where malaria infection was more frequent in the past. It is apparent that in addition to malaria some other factors also play a selective role.