LEISHMANIA - SEX, LIES AND KARYOTYPE

The exploration of the genome of the trypanosomatid protozoan Leishmania has been difficult until recently owing to a number of obstacles, not least our ignorance of the ploidy and of the number of chromosomes (as in many other protozoa, the latter do not condense during mitosis), the uncertainty of the species concept in these allegedly asexual protozoa and the absence of classical genetic studies. Here, Patrick Bastien, Christine Blaineau and Michel Pages discuss the advances in this field brought about by the advent of molecular biology and its techniques, with an emphasis on ploidy and genetic exchange. In particular, they discuss the data from pulsed field gel electrophoresis (PFGE). When coupled with DNA restriction analysis, PFGE constitutes a powerful tool for the direct examination of chromosomes of protozoa.