Our study showed that mRNA expressions of ALDH1B1, ALDH1L1, ALDH2, ALDH4A1, ALDH6A1, ALDH7A1, ALDH8A1, and ALDH9A1 were significantly lower in HCC tissues compared to normal tissues from the Oncomine database. The gene discussed is ALDH7A1; the disease is hepatocellular carcinoma.