Infantile cardiomyopathy caused by the T14709C mutation in the mitochondrial tRNA glutamic acid gene.
A 6-week-old child presented with hypotonia, myopathy, and a rapidly worsening dilated cardiomyopathy with severe atrial and ventricular arrhythmias and pulmonary hypertension, which proved fatal at age 3 months. Biochemical analysis showed a combined deficiency of the enzymatic activities of complexes I and IV and molecular studies identified a T14709C mutation in the mitochondrial tRNA glutamic acid gene. A review of symptomatology in patients with this mutation shows that it mainly presents in childhood or young adults with mild myopathy and diabetes mellitus. Infants with a high, nearly homoplasmic mutant load can present with more severe symptoms including cardiomyopathy. Families with this mitochondrial DNA mutation should be aware that increased mutant load in a subsequent generation may result in severe and often fatal cardiac symptoms.
Van Hove
Johan L K
JL
Department of Pediatrics, The University of Colorado at Denver Health Sciences Center and The Children's Hospital, Denver, CO 80045, USA. Johan.Vanhove@uchsc.edu
Freehauf
Cynthia
C
Miyamoto
Shelley
S
Vladutiu
Georgirene D
GD
Pancrudo
Jacklyn
J
Bonilla
Eduardo
E
Lovell
Mark A
MA
Mierau
Gary W
GW
Thomas
Janet A
JA
Shanske
Sara
S
D009202:Cardiomyopathies / Q000209:etiology* / Q000503:physiopathology; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D007223:Infant; D028361:Mitochondrial Diseases / Q000235:genetics*; D009154:Mutation; D012352:RNA, Transfer, Glu / Q000235:genetics*
D012352:RNA, Transfer, Glu