Atypical early onset of diabetes, deafness and lung cancer in a male patient with mitochondrial mutations in peripheral mononuclear cells.

As mitochondria play a major role in the conversion of dietary calories into usable energy, generating reactive oxygen species as a toxic byproduct, mitochondrial dysfunction plays a role in a wide range of age-related disorders and various forms of cancer. The present report concerns a heavy smoker who died of lung cancer at age 40. He also developed progressive diabetes and sensory hearing loss. Mitochondrial DNA sequence analysis revealed four mutations in peripheral mononuclear cells. Three were novel point mutations, including a mutation in ATP synthase F0 subunit 6 (ATP6). Mitochondrial mutations and smoking may have contributed to the development of atypical early onset of senescence-related diseases in this case.