Imbalanced distribution of Plasmodium falciparum MSP-1 genotypes related to sickle-cell trait.
Mol Med
; 3(9): 581-92, 1997 Sep.
Article
em En
| MEDLINE
| ID: mdl-9323709
ABSTRACT
BACKGROUND:
The sickle-cell trait protects against severe Plasmodium falciparum malaria and reduces susceptibility to mild malaria but does not prevent infection. The exact mechanism of this protection remains unclear. We have hypothesized that AS individuals are protected by virtue of being less susceptible to a subset of parasite strains; thus we compared some genetic characteristics of parasites infecting AS and AA subjects. MATERIALS ANDMETHODS:
Blood was collected from asymptomatic individuals living in two different regions of Africa. The polymorphic MSP-1 and MSP-2 loci were genotyped using a PCR-based methodology. Individual alleles were identified by size polymorphism, amplification using family-specific primers, and hybridization using family-specific probes. Multivariate logistic regression was used to analyze allele distribution.RESULTS:
In Senegalese carriers, age and hemoglobin type influenced differently the distribution of the three MSP-1 families and had an impact on distinct individual alleles, whereas the distribution of MSP-2 alleles was marginally affected. There was no influence of other genetic traits, including the HLA Bw53 genotype, or factors such as place of residence within the village. In a cohort of Gabonese schoolchildren in which the influence of age was abrogated, a similar imbalance in the MSP-1 allelic distribution but not of MSP-2 allelic distribution by hemoglobin type was observed.CONCLUSIONS:
The influence of the host's hemoglobin type on P. falciparum genotypes suggests that parasite fitness for a specific host is strain-dependent, which is consistent with our hypothesis that innate resistance might result from reduced fitness of some parasite strains for individuals with sickle-cell traits.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Plasmodium falciparum
/
Precursores de Proteínas
/
Traço Falciforme
/
Hemoglobina A
/
Hemoglobina Falciforme
/
Proteínas de Protozoários
/
Malária Falciparum
Tipo de estudo:
Prognostic_studies
Limite:
Adolescent
/
Adult
/
Aged
/
Animals
/
Child
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Child, preschool
/
Female
/
Humans
/
Infant
/
Male
País como assunto:
Africa
Idioma:
En
Ano de publicação:
1997
Tipo de documento:
Article