High-GC primers are useful in RAPD analysis of fungi.

For genetic analysis of fungal DNAs, we have modified the RAPD method to use primers with G + C contents of 80-100%. In RAPD analysis of Puccinia graminis f. sp. tritici DNAs, these primers generated twice the number of both amplification products per primer and polymorphisms among isolates as compared to the standard 60-70% G + C primers. With respect to segregation and genetic similarity, RAPD markers generated by the high-GC primers behaved as do RAPD markers produced by the standard primers. These high-GC primers also yielded increased numbers of amplification products in RAPDs on the DNAs of a broad range of other fungi.