A study performed in Mozambique shows regional heterogeneity in the prevalence of the G6PD enzyme

A study co-led by researchers from ISGlobal and the Health Research Center of Manhiça (CISM) investigates the frequency of individuals deficient for an enzyme (called G6PD) and show there is regional heterogeneity. These results are relevant to the design of studies withcertain antimalarial drugs that can trigger acute haemolitic anemia among G6PD-deficient individuals. The project was performed within the framework of the Mozambican Alliance for Malaria Elimination (MALTEM), an initiative supported by the “la Caixa” Foundaton and the Bill & Melinda Gates Foundation, and led by the Mozambican Ministry of Health in collaboration with ISGlobal and CISM.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked genetic anomaly that affects more than 400 million people worldwide. It is believed that G6PD deficiency may confer resistance to infection by Plasmodium, the parasite that causes malaria, which would explain the high prevalence of such anomaly in high malaria-endemic countries. However, although most G6PD deficient individuals do not manifest symptoms, they can develop haemolytic anemia under certain conditions including the administration of chemicals such as primaquine, an antimalarial drug highly effective in eliminating the parasite stage responsible for its transmission.

The aim of this study was to determine the prevalence of G6PD deficiency in different regions of Mozambique, a highly malaria-endemic country. For this, they studied enzyme expression in more than 2,000 school children in the north, center and south of the country. They found that prevalence levels are high and comparable to those described for other malaria-endemic countries, but that they vary considerably across the country, with the highest levels in the center and southern regions. This heterogeneity could be partly explained by the ethnical differences within the country, according to Pedro Aíde, principal investigator of the study.

“These results should be taken in consideration when designing strategies that involve antimalarial drugs such as primaquine, which may trigger haemolitic anemia in patients deficient for this enzyme”, explains Beatriz Galatas, ISGlobal researcher and first author of the study.