It has been previously reported that there are many chromosomal arms having frequent loss of heterozygosity [48], such as 1p, 3p, 4p, 4q, 5q, 8p, 9p (p16), 9q, 10p, 10q, 13q (Rb), 15q, 17p (p53), 18q, 19p, Xp, and Xq, in frequency order for lung cancer [9,45,46,49]. The gene discussed is RB1; the disease is lung cancer.