Wild isolates of Plasmodium falciparum from India show restricted polymorphism in T-helper cell epitopes of the circumsporozoite protein.

Genetic polymorphism in T-helper cell epitopic regions of circumsporozoite protein of 148 Plasmodium falciparum isolates from different epidemic and endemic regions of India has been analyzed by polymerase chain reaction and sequencing. The variation has been found to be regionally unbiased in the sense that identical sequence variation has been found in different regions of India. The variation has also been found to be restricted and could be categorized into four groups.

Genetic diversity of T-helper cell epitopic regions of circumsporozoite protein of Plasmodium falciparum isolates from India.

Genetic variation in the T-helper cell epitopic regions (Th2R and Th3R) of circumsporozoite protein of 135 Plasmodium falciparum isolates collected from different epidemic and endemic regions of India was studied. Variation in the Th2R and Th3R regions was found to exhibit restricted polymorphism and can be grouped. The variations were not regionally biased, as different isolates collected from different regions were found to belong to the same group.