Pituitary tumors or non-tumorigenic pituitary tissues were sampled from 15-month-old mice, and genomic DNA was extracted. DNA samples from livers of each mice were also prepared as non-tumorigenic controls. The wild-type and mutant alleles of Men1 were amplified by PCR (95°C, 1 min; 95°C, 30 s; 60°C, 30 s; 72°C, 1 min, for 35 cycles; 72°C, 10 min; 4°C hold) , which yielded 300-bp and 638-bp amplicons, respectively. The three primers used for the reactions were oIMR1484: CCCACATCCAGTCCCTCTTCAGCT; oIMR1485: CCCTCTGGCTATTCAATGGCAGGG; oIMR1486: CATAAAATCGCAGCAGGTGGGCAA, as suggested by JAX.