A HAPPY map of Cryptosporidium parvum.. Cryptosporidium parvum

Intact genomic DNA is broken by irradiation to give a pool of random fragments, which are size selected by PFGE. A mapping panel of 96 aliquots is taken from this pool. Each aliquot contains ~1 haploid genome's worth of DNA, so each marker is present in only a subset of the aliquots. The panel is pre-amplified a few hundred-fold by primer extension preamplification (PEP). Subfractions of the pre-amplified panel are screened for specific markers using nested PCR. Markers which cosegregate frequently are assumed to be tightly linked on the same fragment of DNA. The Cryptosporidium parvum map was constructed by examining cosegregation frequencies between all markers.