MULTIPLE GENES CODE FOR HIGH-MOLECULAR-MASS RHOPTRY PROTEINS OF PLASMODIUM-YOELII

We have examined the number of genes coding for a group of high-molecu lar-mass rhoptry protein(s) in the malaria parasite Plasmodium yoelii, and studied variation in the gene family within the parasite's genome . A region of the genes was amplified using oligonucleotides based on conserved DNA sequences and the products cloned. The sequences could b e divided into 7 groups by restriction-fragment-length polymorphism. F urther variation was detected by sequence analysis; 11 different seque nces were detected in the 16 clones analyzed. The genes in the family were distributed on 6 chromosomes probably at 9 or more loci.