Together, these mutations point to a complete loss of the wildtype alleles of ATG7. In addition, we conducted a population study of ATG7 polymorphisms associated with CCA in the Icelandic population and identified a polymorphic variant of ATG7 (NM_001349232.2: c.1591C>G p.Asp522Glu (p.D522E)) that was associated with elevated risk of developing this cancer. Here, ATG7 is linked to cholangiocarcinoma.