For the chronic hepatitis B group, the median value of the serum AFP level was 2.1 ng/mL, 3.2 ng/mL, 6.6 ng/mL, and 42.7 ng/mL in the chronic hepatitis group with a normal ALT level, 1 upper limit of normal (ULN) < ALT level ≤ 2 ULN, 2 ULN < ALT level ≤ 5 ULN, and ALT level > 5 ULN, respectively. The gene discussed is AFP; the disease is chronic hepatitis B virus infection.