Chromosomal rearrangements associated with morphological mutants provide a means for genetic variation of Candida albicans

At frequencies as high as 1.4%, the pathogenic yeast Candida albicans spontaneously gave rise to morphological mutants exhibiting more than 20 different types of abnormal colonies; approximately two-thirds of the mutants were stable, while the other one-third were unstable and produced mixtures of different colonial forms at very high rates. Abnormal electrophoretic karyotypes were observed for all of the 14 mutants that were examined, indicating that they were associated with different types of single and multiple gross chromosomal rearrangements. Because C. albicans is asexual and does not go through a meiotic cycle, we suggest that the high frequency of chromosomal rearrangements provides a means for genetic variation in this organism.