a1 Queensland Institute of Medical Research, Brisbane, Australia
a2 Research Institute for Tropical Medicine, Metro Manila, Philippines
a3 Guang Xi Institute of Parasitic Diseases Control, Nanning, GuangXi, People's Republic of China
The diversity in a 925 bp portion of the Plasmodium vivax MSA1 gene in isolates from the Philippines, China, the Solomon Islands and Papua New Guinea was investigated. A total of 74 base pair changes was found in the amplified fragment from 18 isolates. Most of these changes were single or double base pair substitutions. In several regions, these point changes were tightly linked with one set always present or always absent in the different isolates. Seven such blocks were identified. These blocks were present in different combinations in the different isolates indicating that extensive intragenic recombination has occurred.
(Received August 11 1992)
(Revised October 07 1992)
(Accepted October 08 1992)