A SET OF ELECTROPHORETIC MOLECULAR MARKERS FOR STRAIN TYPING AND POPULATION GENETIC-STUDIES OF HISTOPLASMA-CAPSULATUM

A set of eleven biallelic and three multiallelic molecular markers hav e been developed to analyze populations of Histoplasma capsulatum. All markers are amplified by polymerase chain reaction (PCR) and can be r eadily scored using minimal amounts of template DNA. The 11 biallelic loci have polymorphic restriction endonuclease sites or small insertio ns or deletions which may be assessed by agarose gel electrophoresis. These markers are inherited in an unambiguous manner and are ideal for assessing structure and gene flow within US populations of H. capsula tum, but are monomorphic in non-US populations. Both length and sequen ce variation are present in the multiallelic loci, which can be scored by direct sequencing, polyacrylamide gel electrophoresis, or single-s trand conformation polymorphism (SSCP): As they are hypervariable, the multiallelic loci can be used to type isolates and to assess the leve l of genetic variation within populations. Preliminary results indicat e that the three multiallelic markers presented are sufficient to dist inguish isolates at the individual level and are polymorphic in both U S and non-US populations. This collection of molecular markers will be a useful tool in population and epidemiology studies of H. capsulatum .