All reactions were performed in a total volume of 50 μL with 0.1 mM dNTP, 2.5 U Taq DNA polymerase (Life Technologies, Gaithersburg, MD), and 5 to 10 pmol each primer. PCR was performed in a HYBAID Thermal Reactor (Labnet, Woodbridge, NJ) with an elongation temperature of 72° and a denaturation temperature of 95°. When 2 annealing temperatures (AT) are given, A is the primary AT used for the specified number of cycles and B is the AT used for the completion of the PCR reaction. Oligonucleotide sequences are given 5′ to 3′, with the uppercase letters representing the portion that is complementary to regions of the URO-D locus. Lowercase portions of the primers correspond to the M13 reverse primer that were incorporated into the PCR product to facilitate sequencing.