Chromosome size variation in the malaria parasite of rodents, Plasmodium chabaudi.

Pulsed field gradient gel electrophoresis has been used to identify at least 10 large DNA fragments in the genome of the rodent malaria species Plasmodium chabaudi. The fragments range in size from approximately 650 to 5000 kb. All the fragments contain sequences homologous to a P. berghei telomere probe, suggesting that they represent intact chromosomes. Ribosomal RNA genes and P. chabaudi cDNA sequences have been mapped to specific fragments. The fragments vary in size in different cloned isolates of the parasite. In a cross between two cloned parasites differing in the sizes of chromosomes 4 and 5, independent segregation of each chromosome occurred during meiosis.