The Delta-like 1 homolog (DLK1) is a transmembrane protein containing six epidermal growth factor repeats. It is involved in the differentiation of several cell types, including adipocytes and is also thought to be a tumor suppressor. The DLK1 gene is one of several imprinted genes located in a region on chromosome 14q32, certain mutations in this imprinted region can cause phenotypes similar to maternal and paternal uniparental disomy of chromosome 14 (UPD14). DLK1 is expressed from the paternal allele, a polymorphism within this gene has been associated with child and adolescent obesity.Synonyms: DLK, DLK-1, PREF1, Preadipocyte factor 1, Protein delta homolog 1, pG2