Several mutations in a single gene make malaria resistant to chloroquine

LONDON Tom Wellems in the United States says it's taken him 15 years. David Warhurst in the UK says he's been studying the problem since 1963. Many others have been worrying at the issue at least as long. But now Wellems at the US National Institute for Allergy and Infectious Diseases (NIAID) and colleagues have pinned down the first of the serious drug resistances, chloroquine-resistant P. falciparum malaria, to a group of mutations in a single gene.

Wellems dubs the affected gene pfcrt, coding for a membrane protein — PFCRT — that sits in the wall of the parasite's food vacuole. The nomenclature means "P. falciparum chloroquine-resistance transporter", but exactly what the gene does, and how the mutations affect its action, is still up for research. Nevertheless it seems that its correlation with drug resistance is very close, in strains from all over the world.

David Warhurst, Professor of Protozoal ...