MELAS syndrome: Point mutation at nt 3243 (A3243G) in tRNALeu(UUR) gene of mtDNA.
- Author:
Kee Hyung PARK
;
Seung Hyun KIM
;
Young Joo LEE
;
Hee Tae KIM
;
Ju Han KIM
;
Myung Ho KIM
;
Sung Sup PARK
- Publication Type:Original Article
- Keywords:
MELAS;
Mitochondrial DNA;
Point mutation
- MeSH:
Acidosis, Lactic;
Adolescent;
Biopsy;
Brain;
Diagnosis;
DNA, Mitochondrial*;
Glycogen;
Hemianopsia;
Humans;
Hypesthesia;
Lactic Acid;
Leukocytes;
Magnetic Resonance Imaging;
Male;
MELAS Syndrome*;
Mitochondria;
Molecular Biology;
Mothers;
Neurologic Examination;
Paresis;
Point Mutation*;
Thalamus;
Visual Fields
- From:Journal of the Korean Neurological Association
1998;16(4):585-589
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
MELAS (Mitochondrial Encephalomyopathy with Lactic acidosis, and Stroke-like episodes) is a major maternally inherited mitochondrial(mt) encephalopathy, a disease in which 80% of cases are associated with mtDNA point mutation (nt A3243G in tRNALeu(UUR)). We report a case of MELAS syndrome confirmed by typical clinical presentation, muscle biopsy, and molecular genetic diagnosis. A patient was 14-year-old male presenting repeated episode of right hemiparesis and visual field defect. He is exhibited a short stature with dull appearance. On neurologic examination, right homonymous hemianopsia, right hemiparesis, and right side hypesthesia are noted. Brain MRI showed multiple signal changes lesion in left thalamus, right occipital and both temporal regions. Level of lactic acid in serum and CSF was highly increased. Ragged red fibers were shown in the modified Gomori-Trichrome staining, and electromicroscopic finding showed on accumulation of variable sized mitochondrias and glycogen particles in some areas of subsarcolemmal and interfibrillar areas. The mitochondrial tRNALeu(UUR) 3243 A to G mutation was identified by PCR/restriction endonuclease and sequencing. The ratio of mutation in leukocytes of proband and proband's mother was 50% and 10%, respectively. We report a case of MELAS syndromes showing mitochondrial tRNALeu(UUR) 3243 A to G mutation.
