1. ¹Génétique et Immunologie des Maladies Parasitaires, INSERM U399, Laboratoire de Parasitologie et Mycologie, Faculté de Médecine de La Timone, Marseille, France
2. ²Génétique Humaine des Maladies Infectieuses, INSERM U550, Faculté de Médecine de Necker, Paris, France
3. ³Department of Microbiology and Parasitology, Faculty of Medicine, University of Khartoum, Khartoum, Sudan
4. ⁴University of Gezira, Wad Medani, Sudan

Correspondence: Dr A Dessein, INSERM U399, Immunology and Genetics of Parasitic Disease, Faculté de Médecine de La Timone, 27 Bd Jean Moulin, 13385 Marseille Cédex 5, France. E-mail: alain.dessein@medecine.univ-mrs.fr

Abstract

There is some evidence showing that genetic factors are involved in human susceptibility to parasitic diseases such as schistosomiasis and malaria. Studies have shown that the Nramp1 and H-2 genes are implicated in the control of Leishmania donovani infection in mice. We sought genetic loci involved in the control of susceptibility to visceral disease caused by L. donovani in humans. We studied 37 families with at least two affected sibs living in a village in eastern Sudan, where an outbreak of visceral leishmaniasis occurred between 1995 and 2000. The genetic markers located in five chromosomal regions containing candidate genes were typed: 2q35 (NRAMP1), 5q31–q33 (Th2 cytokine cluster), 6p21 (HLA/TNF-), 6q23 (INFGRI) and 12q15 (INF-). Linkage (multipoint lod-score=1.08; P=0.01) was observed for the 5'(CA) repeat polymorphism in the NRAMP1 promoter. This suggests that genetic variations of this gene affect susceptibility to visceral leishmaniasis in this population.