The G6PD gene provides the instructions for marking the glucose-6-phosphate dehydrogenase (G6PDH) enzyme ¹. G6PDH is a cytosolic enzyme located on the long arm of the X-chromosome of bodily cells and so is an inherited x-linked disorder. G6PDH is involved in the normal processing of carbohydrate and the prevention of cellular damage from reactive oxygen species (ROS). In doing so, G6PDH provides substrates to prevent oxidative damage. G6PDH plays a critical role in red blood cells, protecting them from damage and premature destruction. The two main products of G6PDH are:  ribose-5-phosphatase which is important for DNA, the chemical cousin of RNA; and NADPH which protects the body from ROS ^{1, 2}.

Of all malaria cases reported in Latin America and the Caribbean, 42% are attributed to Brazil. However, in recent years, progress has been made towards the elimination of the malaria burden, reaching the lowest levels in the past 35 years (143, 910 cases and 41 confirmed malaria-related deaths). Whilst the transmission area of malaria has significantly reduced, 99.5% of Brazil’s malaria burden is attributed to the Amazon Basin ³. The predominant contributor to the malaria outbreak in Brazil is attributed to the plasmodium vivax parasites which can cause severe and fatal complications in glucose-6-phosphate dehydrogenase (G6PDH) deficient individuals. Individuals infected with malaria are treated with primaquine, however, in G6PDH deficient individuals, this treatment can induce haemolytic anaemia, and so, G6PDH screening is vital ⁴.

A Brazilian study, published in the Malaria Journal prospectively evaluated 516 male volunteers within the Alto do Juruá, an area characterized by a high prevalence of plasmodium vivax, to determine the prevalence of G6PDH. The study found that 4.5% of the study group were G6PDH deficient and were at a high risk of haemolytic anaemia if treated with primaquine. As such, the routine screening of G6PDH deficiency in Brazil to personalize the treatment of patients with vivax malaria, is crucial for malaria elimination ⁴.