Glutathione reductase in the south-western province of Saudi Arabia--genetic variation vs. acquired deficiency.

The activity of glutathione reductase (GR) is closely associated with the riboflavin level in diet. Dietary deficiency of this water-soluble vitamin causes glutathione reductase deficiency. Furthermore, a variable frequency of GR variants with reduced activity has been reported in several populations. In an attempt to determine GR deficiency due to genetic (GR variant) and acquired causes (riboflavin deficiency), red cell GR activity was estimated in 461 male and female Saudis from the South-Western province of Saudi Arabia. The frequency of genetic GR deficiency (GR variant) was 24.5% in Saudi males and 20.3% in females. The frequency of acquired GR deficiency (riboflavin deficiency) was 17.8% and 22.4%, respectively. Interaction between genetic GR deficiency and other genetic abnormalities, i.e. sickle cell gene and glucose-6-phosphate dehydrogenase deficiency were also estimated. No specific link could be demonstrated.