HPRT1 and thyroid cancer, nonmedullary, 2: In males with PTC (Fig. 5-2A\B), PDTC (Fig. 5-2E\F), and FTC (Fig. 5-2C\D), HPRT1 was the best reference gene, while SYMPK was the best in males with ATC (Fig. 5-2G\H).