We assessed OR4F3 and OR4F17 copy number levels by absolute qPCR in healthy controls (Con, n = 5), chronic hepatitis B patients (CHB, n = 10), hepatitis B virus-liver cirrhosis patients (HBV-LC, n = 10), and hepatitis B virus- HCC patients (HBV-HCC, n = 10). Here, OR4F3 is linked to chronic hepatitis B virus infection.