DNA ligase
Genetic deficiencies in human DNA ligases have been associated with clinical syndromes marked by immunodeficiency, radiation sensitivity, and developmental abnormalities,  LIG4 syndrome (Ligase IV syndrome) is a rare disease associated with mutations in DNA ligase 4 and interferes with dsDNA break-repair mechanisms. Ligase IV syndrome causes immunodeficiency in individuals and is commonly associated with microcephaly and marrow hypoplasia. A list of prevalent diseases caused by lack of or malfunctioning of DNA ligase is as follows.