PURPOSE: We report an unusual case of Leber hereditary optic neuropathy presenting with optic disc hyperfluorescence. CASE SUMMARY: A 17-year-old male with sequential painless visual loss 3 weeks apart affecting first the left and then the right eye presented to our neuro-ophthalmology clinic. His best-corrected visual acuity was counting fingers in the right eye and 0.32 in the left eye. Fundus examination showed mild optic disc edema and hyperemia in both eyes, which were worse in the right eye. Fluorescein angiography revealed dye leakage from the right optic disc in the late phase. The results of magnetic resonance imaging of the brain and spinal cord were normal, and lumbar puncture study was unremarkable. Mitochondrial DNA sequencing revealed a pathognomonic 11778 mutation for Leber hereditary optic neuropathy. His vision deteriorated to 0.03 in both eyes 6 months later, but slowly started to improve 11 months after onset. At 2 years, his corrected visual acuity was 0.2 in both eyes. CONCLUSIONS: To our knowledge, this is the first report of optic disc hyperfluorescence in Leber hereditary optic neuropathy. This finding suggests that this mitochondrial optic neuropathy can masquerade as optic neuritis.
Adolescent ; Brain ; DNA, Mitochondrial ; Edema ; Fingers ; Fluorescein Angiography ; Humans ; Hyperemia ; Magnetic Resonance Imaging ; Male ; Optic Atrophy ; Optic Atrophy, Hereditary, Leber ; Optic Nerve Diseases ; Optic Neuritis ; Spinal Cord ; Spinal Puncture ; Visual Acuity

Quality control for genetic analysis has become more important with a drastic increase in testing volume and clinical demands. The molecular diagnostics division of the Korean Association of Quality Assurance for Clinical Laboratory conducted two trials in 2017 on the basis of molecular diagnostics surveys, involving 53 laboratories. The molecular diagnostics surveys included 37 tests: gene rearrangement tests for leukemia (BCR-ABL1, PML-RARA, AML1-ETO, and TEL-AML1), genetic tests for Janus kinase 2, FMS-like tyrosine kinase 3-internal tandem duplication, FMS-like tyrosine kinase 3-tyrosine kinase domain, nucleophosmin, cancer-associated genes (KRAS, EGFR, KIT, and BRAF), hereditary breast and ovarian cancer genes (BRCA1 and BRCA2), Li-Fraumeni syndrome (TP53), Wilson disease (ATP7B), achondroplasia (FGFR3), hearing loss and deafness (GJB2), Avellino (TGFBI), multiple endocrine neoplasia 2 (RET), Huntington disease, spinocerebellar ataxia, spinal and bulbar muscular atrophy, mitochondrial encephalopathy with lactic acidosis and stroke-like episodes, myoclonic epilepsy ragged red fibre, Leber hereditary optic neuropathy, Prader-raderd Angelman syndrome, Duchenne muscular dystrophy, spinal muscular atrophy, fragile X syndrome, apolipoprotein E genotyping, methylenetetrahydrofolate reductase genotyping, and ABO genotyping. Molecular genetic surveys revealed excellent results for most participants. The external quality assessment program for genetic analysis in 2017 proved useful for continuous education and the evaluation of quality improvement.
Achondroplasia ; Acidosis, Lactic ; Angelman Syndrome ; Apolipoproteins ; Brain Diseases ; Breast ; Deafness ; Education ; Epilepsies, Myoclonic ; Fragile X Syndrome ; Gene Rearrangement ; Hearing Loss ; Hepatolenticular Degeneration ; Huntington Disease ; Janus Kinase 2 ; Korea* ; Laboratory Proficiency Testing ; Leukemia ; Li-Fraumeni Syndrome ; Methylenetetrahydrofolate Reductase (NADPH2) ; Molecular Biology ; Multiple Endocrine Neoplasia ; Muscular Atrophy, Spinal ; Muscular Disorders, Atrophic ; Muscular Dystrophy, Duchenne ; Optic Atrophy, Hereditary, Leber ; Ovarian Neoplasms ; Pathology, Molecular* ; Phosphotransferases ; Quality Control ; Quality Improvement ; Spinocerebellar Ataxias ; Vascular Endothelial Growth Factor Receptor-1

PURPOSE: Leber hereditary optic neuropathy (LHON) is one of the most common hereditary optic neuropathies caused by mutations of mitochondrial DNA. Three common mitochondrial mutations causing LHON are m.3460, m.11778, and m.14484. We report a rare mutation of the mitochondrial tRNA (Leu [UUR]) gene (MT-TL1) (m.3268 A > G) in a patient with bilateral optic atrophy. CASE SUMMARY: A 59-year-old female diagnosed with glaucoma 3 years earlier at a community eye clinic presented to our neuro-ophthalmology clinic. On examination, her best corrected visual acuity was 0.4 in the right eye and 0.7 in the left eye, and optic atrophy was noticed in both eyes. Optical coherence tomography revealed retinal nerve fiber layer (RNFL) thinning in both eyes; average RNFL thickness was 52 µm in the right eye and 44 µm in the left eye, but the papillomacular bundle was relatively preserved in both eyes. Goldmann perimetry demonstrated peripheral visual field defects, mostly involving superotemporal visual field in both eyes. Mitochondrial DNA mutation test showed an unusual mutation in MT-TL1 gene seemingly related to this optic neuropathy. CONCLUSIONS: We found a rare mutation (m.3268 A > G) of the mitochondrial DNA in a patient having bilateral optic atrophy, which led to the diagnosis of LHON. There have been previous reports about mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) and infantile myopathy caused by MT-TL1 mutation, but this is the first case of LHON associated with the same mutation. In this case of LHON associated with MT-TL1 mutation, atypical clinical features were observed with a relatively mild phenotype and peripheral visual field defects.
Diagnosis ; DNA, Mitochondrial ; Female ; Glaucoma* ; Humans ; MELAS Syndrome ; Middle Aged ; Muscular Diseases ; Nerve Fibers ; Optic Atrophy ; Optic Atrophy, Hereditary, Leber* ; Optic Nerve Diseases ; Phenotype ; Retinaldehyde ; RNA, Transfer ; Tomography, Optical Coherence ; Visual Acuity ; Visual Field Tests ; Visual Fields

The Diagnostic Genetics Subcommittee of Korean Association of External Quality Assessment Service conducted two trials in 2015 based on cytogenetics and molecular genetics surveys. A total of 43 laboratories participated in the chromosome surveys, 31 laboratories participated in the fluorescence in situ hybridization surveys, and 133 laboratories participated in the molecular genetics surveys. All except one laboratory showed acceptable results in the cytogenetics surveys. The molecular genetics surveys included the following tests: Mycobacterium tuberculosis detection, hepatitis B and C virus detection and quantification, human papilloma virus genotyping, gene rearrangement tests for leukaemias and lymphomas, genetic tests for JAK2, FMS-like tyrosine kinase 3, nucleophosmin, cancer-associated genes (KRAS, EGFR, KIT, and BRAF), hereditary breast and ovarian cancer genes (BRCA1 and BRCA2), Li-Fraumeni syndrome (TP53), Wilson disease (ATP7B), achondroplasia (FGFR3), hearing loss and deafness (GJB2 ), multiple endocrine neoplasia 2 (RET), Huntington disease, spinocerebellar ataxia, spinal and bulbar muscular atrophy, mitochondrial encephalopathy with lactic acidosis and stroke like episodes, myoclonic epilepsy ragged red fibre, Leber hereditary optic neuropathy, Prader-Willi/Angelman syndrome, Duchenne muscular dystrophy, spinal muscular atrophy, fragile X syndrome (FMR1), apolipoprotein E genotyping, methylenetetrahydrofolate reductase genotyping, ABO genotyping, cytochrome P450 2C9 genotyping, cytochrome P450 2C19 genotyping, and DNA sequencing analysis. The molecular genetics surveys showed excellent results for most of the participants. The external quality assessment program for genetics analysis in 2015 proved to be helpful for continuous education and the evaluation of quality improvement.
Achondroplasia ; Acidosis, Lactic ; Apolipoproteins ; Breast ; Cytochrome P-450 Enzyme System ; Cytogenetics ; Deafness ; Education ; Epilepsies, Myoclonic ; Fluorescence ; fms-Like Tyrosine Kinase 3 ; Fragile X Syndrome ; Gene Rearrangement ; Genetics* ; Hearing Loss ; Hepatitis B ; Hepatolenticular Degeneration ; Humans ; Huntington Disease ; In Situ Hybridization ; Korea* ; Li-Fraumeni Syndrome ; Lymphoma ; Methylenetetrahydrofolate Reductase (NADPH2) ; Molecular Biology ; Multiple Endocrine Neoplasia ; Muscular Atrophy, Spinal ; Muscular Disorders, Atrophic ; Muscular Dystrophy, Duchenne ; Mycobacterium tuberculosis ; Optic Atrophy, Hereditary, Leber ; Ovarian Neoplasms ; Papilloma ; Quality Improvement ; Sequence Analysis, DNA ; Spinocerebellar Ataxias ; Stroke

OBJECTIVETo investigate the role of MT-ND1 m.3635G>A mutation in the pathogenesis of Leber's hereditary optic neuropathy (LHON).

METHODSBiochemical characteristics including the activity of complex Ⅰ, ATP production and oxygen consumption rate among lymphoblastoid cell lines derived from 3 carriers, 3 affected matrilineal relatives of the families and 3 controls were compared.

RESULTSComparison of mitochondrial functions in lymphoblastoid cell lines of the carriers, patients and controls showed a 51.0% decrease in the activity of complex Ⅰ in patients compared with controls (P<0.05). The m.3635G>A mutation has resulted in decreased efficiency of ATP synthesis (P<0.05). Comparison of oxygen consumption rate showed that the basal OCR (P<0.05), ATP-linked OCR (P<0.05) and the maximum OCR (P<0.05) have all reduced to some extent compared with the controls.

CONCLUSIONThese results showed that m.3635G>A, as a LHON-associated mutation, can lead to mitochondrial dysfunction.

Adenosine Triphosphate ; genetics ; Asian Continental Ancestry Group ; genetics ; Female ; Humans ; Male ; Mitochondria ; genetics ; Mutation ; genetics ; NADH Dehydrogenase ; genetics ; Optic Atrophy, Hereditary, Leber ; genetics ; Pedigree

OBJECTIVETo report on clinical, genetic and molecular characterization of two Chinese families with Leber's hereditary optic neuropathy.

METHODSOphthalmological examinations have revealed variable severity and age at onset of visual loss among the probands and other matrilineal relatives of both families. The entire mitochondrial genome of the two probands was amplified with PCR in 24 overlapping fragments using sets of oligonucleotide primers.

RESULTSThe ophthalmological examinations showed that penetrance was 12.5% and 30.0% respectively in the two families. Sequence analysis of the complete mitochondrial genomes in these pedigrees has identified unreported homoplasmic T8821G mutation in the ATPase 6 gene and distinct sets of polymorphisms belonging to haplogroups M10a. The T8821G mutation has occurred at the extremely conserved nucleotide (conventional position 99) of the ATPase6. Thus, this mutation may alter structural formation of ATPase6, thereby leading to failure in the synthesis of ATP involved in visual impairment.

CONCLUSIONAbove observations have suggested that the ATPase6 T8821G mutation may be involved in the pathogenesis of optic neuropathy in these families.

Adolescent ; Asian Continental Ancestry Group ; genetics ; Base Sequence ; China ; DNA, Mitochondrial ; genetics ; Female ; Humans ; Male ; Mitochondrial Proton-Translocating ATPases ; genetics ; Molecular Sequence Data ; Optic Atrophy, Hereditary, Leber ; enzymology ; genetics ; Pedigree ; Point Mutation ; Young Adult

Quality control for genetic tests has become more important as testing volume and clinical demands have increased dramatically. The diagnostic genetics subcommittee of Korean Association of External Quality Assessment Service conducted two trials in 2014 based on cytogenetics and molecular genetics surveys. A total of 44 laboratories participated in the chromosome surveys, 33 laboratories participated in the fl uorescence in situ hybridization (FISH) surveys, and 130 laboratories participated in the molecular genetics surveys as a part of these trials. All laboratories showed acceptable results in the chromosome and FISH surveys. The molecular genetics surveys included various tests: Mycobacterium tuberculosis detection, hepatitis B and C virus detection and quantification, human papilloma virus genotyping, gene rearrangement tests for leukaemia and lymphomas, genetic tests for JAK2, FMS-like tyrosine kinase 3, nucleophosmin, cancer-associated genes (KRAS, EGFR, KIT, and BRAF), hereditary breast and ovarian cancer genes (BRCA1 and BRCA2), Li-Fraumeni syndrome (TP53), Wilson disease (ATP7B), achondroplasia (FGFR3), Huntington disease, spinocerebellar ataxia, spinal and bulbar muscular atrophy, mitochondrial encephalopathy with lactic acidosis and stroke like episodes, myoclonic epilepsy ragged red fibre, Prader-Willi/Angelman syndrome, Duchenne muscular dystrophy, spinal muscular atrophy, fragile X syndrome, nonsyndromic hearing loss and deafness (GJB2), multiple endocrine neoplasia 2 (RET), Leber hereditary optic neuropathy (major mutation), apolipoprotein E genotyping, methylenetetrahydrofolate reductase genotyping, ABO genotyping, and DNA sequencing analysis. Molecular genetic surveys showed excellent results for most of the participants. The external quality assessment program for genetic analysis in 2014 proved to be helpful for continuous education and the evaluation of quality improvement.
Achondroplasia ; Acidosis, Lactic ; Apolipoproteins ; Breast ; Cytogenetics ; Deafness ; Education ; Epilepsies, Myoclonic ; fms-Like Tyrosine Kinase 3 ; Fragile X Syndrome ; Gene Rearrangement ; Genetics* ; Hearing Loss ; Hepatitis B ; Hepatolenticular Degeneration ; Humans ; Huntington Disease ; In Situ Hybridization ; Korea ; Li-Fraumeni Syndrome ; Lymphoma ; Methylenetetrahydrofolate Reductase (NADPH2) ; Molecular Biology ; Molecular Diagnostic Techniques ; Multiple Endocrine Neoplasia ; Muscular Atrophy, Spinal ; Muscular Disorders, Atrophic ; Muscular Dystrophy, Duchenne ; Mycobacterium tuberculosis ; Optic Atrophy, Hereditary, Leber ; Ovarian Neoplasms ; Papilloma ; Quality Assurance, Health Care ; Quality Control ; Quality Improvement ; Sequence Analysis, DNA ; Spinocerebellar Ataxias ; Stroke

OBJECTIVETo report on the clinical, genetic and molecular characteristics of three ethnic Han Chinese families affected with Leber's hereditary optic neuropathy (LHON).

METHODSThe three families were all diagnosed with LHON. Ophthalmologic examinations were conducted on the probands . The ND1, ND4 and ND6 genes of the mitochondrial DNA (mtDNA) were amplified with PCR respectively for the screening of three primary mutations G3460A, G11778A and T14484C. The entire mtDNA of the probands were also amplified by PCR.

RESULTSAnalysis of mtDNA in the three pedigrees has failed to find the presence of the three LHON associated mutations but presence of a homoplastic ND1 T3866C mutation in all probands and their matrilineal relatives . The probands had different levels of visual impairment. The penetrance in the three families has been calculated as 12.5%, 11.1% and 33.3%, respectively. The T3866C mutation has resulted in replacement of isoleucine at position 187 with theronine. The isoleucine at position 187 is located at one of the transmembrane domains of ND1 polypeptide.

CONCLUSIONAbove results have suggested that the ND1 T3866C mutation might have been involved in the pathogenesis of LHON in the three Chinese families studied.

Adolescent ; Asian Continental Ancestry Group ; ethnology ; genetics ; Base Sequence ; Child ; Female ; Humans ; Male ; Mitochondria ; genetics ; Molecular Sequence Data ; NADH Dehydrogenase ; genetics ; Optic Atrophy, Hereditary, Leber ; ethnology ; genetics ; Pedigree ; Point Mutation

OBJECTIVETo explore the application value of next generation sequencing (NGS) in the diagnosis of mitochondrial disorders.

METHODAccording to mitochondrial disease criteria, genomic DNA was extracted using standard procedure from peripheral venous blood of patients with suspected mitochondrial disease collected from neurological department of Beijing Children's Hospital Affiliated to Capital Medical University between October 2012 and February 2014. Targeted NGS to capture and sequence the entire mtDNA and exons of the 1 000 nuclear genes related to mitochondrial structure and function. Clinical data were collected from patients diagnosed at a molecular level, then clinical features and the relationship between genotype and phenotype were analyzed.

RESULTMutation was detected in 21 of 70 patients with suspected mitochondrial disease, in whom 10 harbored mtDNA mutation, while 11 nuclear DNA (nDNA) mutation. In 21 patients, 1 was diagnosed congenital myasthenic syndrome with episodic apnea due to CHAT gene p.I187T homozygous mutation, and 20 were diagnosed mitochondrial disease, in which 10 were Leigh syndrome, 4 were mitochondrial encephalomyopathy with lactic acidosis and stroke like episodes syndrome, 3 were Leber hereditary optic neuropathy (LHON) and LHON plus, 2 were mitochondrial DNA depletion syndrome and 1 was unknown. All the mtDNA mutations were point mutations, which contained A3243G, G3460A, G11778A, T14484C, T14502C and T14487C. Ten mitochondrial disease patients harbored homozygous or compound heterozygous mutations in 5 genes previously shown to cause disease: SURF1, PDHA1, NDUFV1, SUCLA2 and SUCLG1, which had 14 mutations, and 7 of the 14 mutations have not been reported.

CONCLUSIONNGS has a certain application value in the diagnosis of mitochondrial diseases, especially in Leigh syndrome atypical mitochondrial syndrome and rare mitochondrial disorders.

Child ; DNA, Mitochondrial ; genetics ; High-Throughput Nucleotide Sequencing ; Homozygote ; Humans ; Leigh Disease ; Mitochondrial Diseases ; diagnosis ; Mitochondrial Encephalomyopathies ; Mutation ; Optic Atrophy, Hereditary, Leber ; Phenotype ; Point Mutation ; Sequence Analysis, DNA

PURPOSE: In order to evaluate the clinical features and visual prognosis of Leber's hereditary optic neuropathy (LHON) associated with T14484C mitochondrial DNA (mtDNA) mutation in Korean patients. METHODS: To evaluate the clinical feature of Korean LHON patients with T14484C mtDNA mutation, a retrospective chart review was performed on 14 patients who visited our clinic with the chief complaint of decreased visual acuity. RESULTS: All of the 14 patients experienced a significant decrease in visual acuity during the follow-up period. Eight of these patients (57%) showed an improvement in visual acuity of 20/50 or better in one or both eyes, and the remaining six patients (43%) showed visual acuities of 20/200 or worse in both eyes at the final follow-up. When the symptoms aggravated, ten patients (71%) showed central scotoma or cecocentral scotoma. Eleven of 12 patients (92%) who had undergone the Ishihara color vision test showed dyschromatopsia in the aggravated stage. Four patients had dyschromatopsia and three patients had central scotoma in both eyes even after visual recovery. There were no statistically significant differences in the age of onset or the nadir of visual acuity between the good visual recovery group and the non-recovery group (p > 0.05). CONCLUSIONS: Korean LHON patients with the T14484C mutation showed relatively good visual prognosis similar to those of the Caucasian or Japanese patients but with remaining dyschromatopsia or central scotoma after visual recovery.
Age of Onset ; Asian Continental Ancestry Group ; Color Vision ; DNA, Mitochondrial ; Eye ; Follow-Up Studies ; Humans ; Optic Atrophy, Hereditary, Leber ; Prognosis ; Retrospective Studies ; Scotoma ; Visual Acuity