Human tumors and liver cancer cell lines express the product of a fusion between the first 13 exons in the mannosidase α class 2A member 1 gene (MAN2A1) and the last 6 exons in the FER tyrosine kinase gene (FER), called MAN2A1−FER. We investigated whether MAN2A1−FER is expressed by human liver tumors and its role in liver carcinogenesis.