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Lawaly YR, Sakuntabhai A, Marrama L, Konate L, Phimpraphi W, Sokhna C, Tall A, Diène Sarr F, Peerapittayamongkol C, Louicharoen C, Schneider BS, Levescot A, Talman A, Casademont I, Menard D, Trape JF, Rogier C, Kaewkunwal J, Sura T, Nuchprayoon I, Ariey F, Baril L, Singhasivanon P, Mercereau-Puijalon O, Paul R. Heritability of the human infectious reservoir of malaria parasites. PLoS One 2010; 5:e11358. [PMID: 20613877 PMCID: PMC2894056 DOI: 10.1371/journal.pone.0011358] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Accepted: 05/28/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Studies on human genetic factors associated with malaria have hitherto concentrated on their role in susceptibility to and protection from disease. In contrast, virtually no attention has been paid to the role of human genetics in eliciting the production of parasite transmission stages, the gametocytes, and thus enhancing the spread of disease. METHODS AND FINDINGS We analysed four longitudinal family-based cohort studies from Senegal and Thailand followed for 2-8 years and evaluated the relative impact of the human genetic and non-genetic factors on gametocyte production in infections of Plasmodium falciparum or P. vivax. Prevalence and density of gametocyte carriage were evaluated in asymptomatic and symptomatic infections by examination of Giemsa-stained blood smears and/or RT-PCR (for falciparum in one site). A significant human genetic contribution was found to be associated with gametocyte prevalence in asymptomatic P. falciparum infections. By contrast, there was no heritability associated with the production of gametocytes for P. falciparum or P. vivax symptomatic infections. Sickle cell mutation, HbS, was associated with increased gametocyte prevalence but its contribution was small. CONCLUSIONS The existence of a significant human genetic contribution to gametocyte prevalence in asymptomatic infections suggests that candidate gene and genome wide association approaches may be usefully applied to explore the underlying human genetics. Prospective epidemiological studies will provide an opportunity to generate novel and perhaps more epidemiologically pertinent gametocyte data with which similar analyses can be performed and the role of human genetics in parasite transmission ascertained.
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Affiliation(s)
| | - Anavaj Sakuntabhai
- Institut Pasteur, Laboratoire de la Génétique de la réponse aux infections chez l'homme, Paris, France
- Institut Pasteur, Unité de Pathogénie Virale, Paris, France
| | - Laurence Marrama
- Institut Pasteur de Dakar, Unité d'Epidémiologie, Dakar, Senegal
| | - Lassana Konate
- Faculté des Sciences et Techniques, UCAD, Dakar, Senegal
| | - Waraphon Phimpraphi
- Institut Pasteur, Laboratoire de la Génétique de la réponse aux infections chez l'homme, Paris, France
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok Thailand
| | - Cheikh Sokhna
- Institut de Recherche pour le Développement, Laboratoire de Paludologie, Dakar, Senegal
| | - Adama Tall
- Institut Pasteur de Dakar, Unité d'Epidémiologie, Dakar, Senegal
| | | | | | - Chalisa Louicharoen
- Institut Pasteur, Laboratoire de la Génétique de la réponse aux infections chez l'homme, Paris, France
- Inter-Department Program of Biomedical Science, Faculty of Graduate School, Chulalongkorn University, Bangkok, Thailand
| | | | - Anaïs Levescot
- Institut Pasteur, Laboratoire de la Génétique de la réponse aux infections chez l'homme, Paris, France
| | - Arthur Talman
- Unité d'Epidémiologie Moléculaire, Institut Pasteur, Phnom Penh, Cambodia
| | - Isabelle Casademont
- Institut Pasteur, Laboratoire de la Génétique de la réponse aux infections chez l'homme, Paris, France
- Institut Pasteur, Unité de Pathogénie Virale, Paris, France
| | - Didier Menard
- Unité d'Epidémiologie Moléculaire, Institut Pasteur, Phnom Penh, Cambodia
| | - Jean-François Trape
- Institut de Recherche pour le Développement, Laboratoire de Paludologie, Dakar, Senegal
| | - Christophe Rogier
- Institut de Médecine Tropicale du Service de Santé des Armées, Unité de Recherche en Biologie et épidémiologie parasitaires, IFR48, Le Pharo, Marseille, France
| | - Jaranit Kaewkunwal
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok Thailand
| | - Thanyachai Sura
- Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Issarang Nuchprayoon
- Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Frederic Ariey
- Unité d'Epidémiologie Moléculaire, Institut Pasteur, Phnom Penh, Cambodia
| | - Laurence Baril
- Institut Pasteur de Dakar, Unité d'Epidémiologie, Dakar, Senegal
| | - Pratap Singhasivanon
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok Thailand
| | | | - Rick Paul
- Institut Pasteur de Dakar, Laboratoire d'Entomologie Médicale, Dakar, Senegal
- Institut Pasteur, Laboratoire de la Génétique de la réponse aux infections chez l'homme, Paris, France
- Institut Pasteur, Unité de Pathogénie Virale, Paris, France
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Phimpraphi W, Paul R, Witoonpanich B, Turbpaiboon C, Peerapittayamongkol C, Louicharoen C, Casademont I, Tungpradabkul S, Krudsood S, Kaewkunwal J, Sura T, Looareesuwan S, Singhasivanon P, Sakuntabhai A. Heritability of P. falciparum and P. vivax malaria in a Karen population in Thailand. PLoS One 2008; 3:e3887. [PMID: 19060954 PMCID: PMC2588340 DOI: 10.1371/journal.pone.0003887] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2008] [Accepted: 11/12/2008] [Indexed: 11/18/2022] Open
Abstract
The majority of studies concerning malaria host genetics have focused on individual genes that confer protection against rather than susceptibility to malaria. Establishing the relative impact of genetic versus non-genetic factors on malaria infection and disease is essential to focus effort on key determinant factors. This relative contribution has rarely been evaluated for Plasmodium falciparum and almost never for Plasmodium vivax. We conducted a longitudinal cohort study in a Karen population of 3,484 individuals in a region of mesoendemic malaria, Thailand from 1998 to 2005. The number of P. falciparum and P. vivax clinical cases and the parasite density per person were determined. Statistical analyses were performed to account for the influence of environmental factors and the genetic heritability of the phenotypes was calculated using the pedigree-based variance components model. The genetic contribution to the number of clinical episodes resulting from P. falciparum and P. vivax were 10% and 19% respectively. There was also moderate genetic contribution to the maximum and overall parasite trophozoite density phenotypes for both P. falciparum (16%&16%) and P. vivax (15%&13%). These values, for P. falciparum, were similar to those previously observed in a region of much higher transmission intensity in Senegal, West Africa. Although environmental factors play an important role in acquiring an infection, genetics plays a determinant role in the outcome of an infection with either malaria parasite species prior to the development of immunity.
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Affiliation(s)
- Waraphon Phimpraphi
- Institut Pasteur, Laboratoire de la Génétique de la réponse aux infections chez l'homme, Paris, France
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok Thailand
| | - Richard Paul
- Institut Pasteur, Laboratoire de la Génétique de la réponse aux infections chez l'homme, Paris, France
| | - Bhee Witoonpanich
- Institut Pasteur, Laboratoire de la Génétique de la réponse aux infections chez l'homme, Paris, France
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Chairat Turbpaiboon
- Institut Pasteur, Laboratoire de la Génétique de la réponse aux infections chez l'homme, Paris, France
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand
| | | | - Chalisa Louicharoen
- Institut Pasteur, Laboratoire de la Génétique de la réponse aux infections chez l'homme, Paris, France
| | - Isabelle Casademont
- Institut Pasteur, Laboratoire de la Génétique de la réponse aux infections chez l'homme, Paris, France
| | - Sumalee Tungpradabkul
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Srivicha Krudsood
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok Thailand
| | - Jaranit Kaewkunwal
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok Thailand
| | - Thanyachai Sura
- Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Sornchai Looareesuwan
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Pratap Singhasivanon
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok Thailand
| | - Anavaj Sakuntabhai
- Institut Pasteur, Laboratoire de la Génétique de la réponse aux infections chez l'homme, Paris, France
- Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
- * E-mail:
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