TY - JOUR
T1 - Polymorphism in the gene encoding the Pfs48/45 antigen of Plasmodium falciparum. XI. Asembo Bay Cohort Project
AU - Escalante, Ananias A.
AU - Grebert, Heather M.
AU - Chaiyaroj, Sansanee C.
AU - Riggione, Flavia
AU - Biswas, Sukla
AU - Nahlen, Bernard L.
AU - Lal, Altaf A.
N1 - Funding Information:
This research is supported in part by grants from the ‘Consejo Venezolano de Investigaciones Cientı́ficas, CONICIT’, (G97000634) and The National Institutes of Health (R01 GM60740-01) to A.A.E. This work was supported in part by the US Agency for International Development grant HRN-60010-A-00-4010-00 to A.A.L.
PY - 2002
Y1 - 2002
N2 - We have investigated the genetic diversity of the gene encoding the transmission-blocking vaccine antigen Pfs48/45 of Plasmodium falciparum parasites from western Kenya and compared it with parasite populations from Thailand, India, and Venezuela. We report 44 complete new sequences. Overall, the antigen is less polymorphic as compared with other pre-erythrocytic and blood stage antigens. Contrary to other P. falciparum antigens, the number of synonymous substitutions per synonymous site exceeds the number of non-synonymous substitutions per non-synonymous site. We have found that the Pfs48/45 gene of Kenyan parasites is more polymorphic than parasites from other geographic origins. Our analysis reveals that positive natural selection is involved in the maintenance of the observed polymorphism. No evidence of intragenic recombination was found. Fst values reveal high levels of gene flow between India and Thailand, however, there are strong constraints in gene flow among Kenyan, Southeast Asian, and Venezuelan parasites. No alleles could be linked to a specific geographic region. The results of this study suggest that this gametocyte antigen, like other asexual blood stage antigens, is under selection pressure.
AB - We have investigated the genetic diversity of the gene encoding the transmission-blocking vaccine antigen Pfs48/45 of Plasmodium falciparum parasites from western Kenya and compared it with parasite populations from Thailand, India, and Venezuela. We report 44 complete new sequences. Overall, the antigen is less polymorphic as compared with other pre-erythrocytic and blood stage antigens. Contrary to other P. falciparum antigens, the number of synonymous substitutions per synonymous site exceeds the number of non-synonymous substitutions per non-synonymous site. We have found that the Pfs48/45 gene of Kenyan parasites is more polymorphic than parasites from other geographic origins. Our analysis reveals that positive natural selection is involved in the maintenance of the observed polymorphism. No evidence of intragenic recombination was found. Fst values reveal high levels of gene flow between India and Thailand, however, there are strong constraints in gene flow among Kenyan, Southeast Asian, and Venezuelan parasites. No alleles could be linked to a specific geographic region. The results of this study suggest that this gametocyte antigen, like other asexual blood stage antigens, is under selection pressure.
KW - Genetic diversity
KW - Geographic variation
KW - Malaria
KW - Plasmodium
KW - Transmission-blocking
KW - Vaccine
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U2 - 10.1016/S0166-6851(01)00386-3
DO - 10.1016/S0166-6851(01)00386-3
M3 - Article
C2 - 11755182
AN - SCOPUS:0036137980
SN - 0166-6851
VL - 119
SP - 17
EP - 22
JO - Molecular and Biochemical Parasitology
JF - Molecular and Biochemical Parasitology
IS - 1
ER -