Characterization of four sequences used as markers in cryptococcus neoformans molecular typing

PCR-fingerprinting using (GACA)4 simple repetitive sequence was adopted as molecular typing method for Cryptococcus neoformans in several studies previously carried out in our Institute. Fingerprinting profiles were characterized by the presence of four major bands (420, 475, 540, 800 bp) which were able to identify four genotypes. In the present study the nucleotide sequence of the four major bands were aligned, by BLASTn and BLASTx algorithms, to the sequences contained in the largest databases available for Cryptococcus neoformans genome. The results showed the exact location of all band sequences either in H99 serotype A genome and in JEC21 serotype D genome. In addition, the sequences of 540 and 420 bp bands were recognized to belong to two different DNA regions coding for functional proteins. In view of the above results the present study contributed to elucidate the identity and the location of the four major bands amplified by PCR fingerprinting with (GACA)4 primer and represent a useful reference for the interpretation of future studies carried out using this typing method.