rs199476112

chrM-11778-G-A

Variant summary

Our verdict is Pathogenic. Variant got 8 ACMG points: 8P and 0B. PS4 PP1_Moderate PS3_Supporting PP3

This summary comes from the ClinGen Evidence Repository: The m.11778G>A (p.R340H) variant in MT-ND4 has been reported in >16 unrelated individuals with primary mitochondrial disease. While this variant is one of the three most common variants associated with Leber Hereditary Optic Neuropathy (LHON; PMID:20301353), affected individuals can also have other features. Indeed, affected individuals have been reported with features including LHON, Leigh syndrome, cerebellar ataxia, migraines, regression, leukoencephalopathy, myoclonus, psychiatric illness, Parkinsonism, axonal neuropathy, multiple sclerosis, and ophthalmoplegia; and this variant has been seen in affected individuals in the homoplasmic and heteroplasmic states (PS4; PMIDs: 3201231, 2575667, 2566021, 2390098, 1635296, 17724295, 18848389, 25917160, 18216301, 17254817, 8902729, 27119776). This variant segregated with disease in multiple affected members in multiple families and several healthy family members had lower to undetectable levels of the variant (PP1_moderate; PMIDs: 27119776, 2390098). There are no confirmed de novo occurrences of this variant to our knowledge. This variant is present in the healthy population, which is to be expected given the known reduced penetrance of this variant. The computational predictor APOGEE gives a consensus rating of pathogenic with a score of 0.97 (Min=0, Max=1), which predicts a damaging effect on gene function (PP3). Cybrid studies supported the functional impact of this variant (PS3_supporting; PMIDs: 10976107, 7763260). This variant meets criteria to be classified as likely pathogenic however this Expert Panel elected to modify the classification to pathogenic given the overwhelming evidence of pathogenicity. Furthermore, the mitochondrial DNA variant specifications are known to not be optimized for pathogenic variants that tend to be homoplasmic in nature and/or have reduced penetrance, such as the common variants associated with LHON. This classification was approved by the NICHD/NINDS U24 Mitochondrial Disease Variant Curation Expert Panel on May 24, 2022. Mitochondrial DNA-specific ACMG/AMP criteria applied (PMID:32906214): PS3_supporting, PS4, PP1_moderate, PP3. LINK:https://erepo.genome.network/evrepo/ui/classification/CA340939/MONDO:0044970/014

• Frequency: Mitomap GenBank: Absent
• Consequence: MT-ND4 ENST00000361381.2 missense
• Scores: Apogee2 Pathogenic 0.93
• Clinical Significance: Pathogenic reviewed by expert panel P:17 O:2 LHON-/-Progressive-Dystonia
• Conservation: PhyloP100: 3.76

Genes affected

MT-ND4 (HGNC:7459): (mitochondrially encoded NADH dehydrogenase 4) Enables NADH dehydrogenase (ubiquinone) activity. Involved in mitochondrial electron transport, NADH to ubiquinone and mitochondrial respiratory chain complex I assembly. Part of mitochondrial respiratory chain complex I. Implicated in Leber hereditary optic neuropathy; Parkinson's disease; macular degeneration; and schizophrenia. Biomarker of Alzheimer's disease. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Pathogenic. Variant got 8 ACMG points.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MT-ND4	ENST00000361381.2	c.1019G>A	p.Arg340His	missense_variant	1/1			P1

Frequencies

GnomAD4 exome Cov.: 0

We have no GnomAD4 genomes data on this position. Probably position not covered by the project.

Gnomad homoplasmic AF: 0.00019 AC: 11 AN: 56423

Gnomad heteroplasmic AF: 0.00023 AC: 13 AN: 56423

Alfa AF: 0.000111 Hom.: 0

Mitomap

LHON-/-Progressive-Dystonia

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:17 Other:2

Revision: reviewed by expert panel

Submissions by phenotype

Leber optic atrophy Pathogenic:11 Other:2

Pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Oct 31, 2018	- -
Pathogenic, criteria provided, single submitter	clinical testing	Mendelics	May 04, 2022	- -
not provided, no classification provided	literature only	GeneReviews	-	This variant is one of the three most common causes of LHON. -
Pathogenic, criteria provided, single submitter	clinical testing	Kasturba Medical College, Manipal, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics, University of Leipzig Medical Center	Feb 01, 2024	Criteria applied: PS4,PM5,PP1_MOD,PS3_SUP,PP3 -
Pathogenic, criteria provided, single submitter	clinical testing	Pediatric Department, Xiangya Hospital, Central South University	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Victorian Clinical Genetics Services, Murdoch Childrens Research Institute	-	A heteroplasmic (76.20%) missense variant has been identified in MT-ND4. This gene encodes a protein subunit of complex I. The variant is predicted to result in a minor amino acid change from arginine to histidine at position 340 of the protein. The arginine at this position has high conservation (MITOMASTER). In silico predictions for this variant are consistently pathogenic (Polyphen, SIFT, HmtDB Disease Score). The variant is present in the MITOMAP population database at a frequency of 0.358%. The variant has been previously described as pathogenic in multiple individuals with Leber hereditary optic neuropathy (LHON) and is considered to be the most common MT-ND4 variant in European and Asian populations. Affected individuals generally have more than 70% heteroplasmy in blood, however the variant is also known to have reduced penetrance, with males more commonly affected than females (ClinVar, GeneReviews, OMIM, PMID: 31932089). This variant has been shown to be maternally inherited (by trio analysis) with a heteroplamic level of 26.70% in this individual's mother. -
not provided, no classification provided	phenotyping only	GenomeConnect, ClinGen	-	GenomeConnect assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. GenomeConnect staff make no attempt to reinterpret the clinical significance of the variant. -
Pathogenic, no assertion criteria provided	clinical testing	Genomics England Pilot Project, Genomics England	-	- -
Pathogenic, no assertion criteria provided	research	Equipe Genetique des Anomalies du Developpement, Université de Bourgogne	Jun 26, 2018	- -
Pathogenic, no assertion criteria provided	clinical testing	Clinical Genetics Laboratory, University Hospital Schleswig-Holstein	Sep 16, 2021	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Dec 01, 2008	- -
Pathogenic, criteria provided, single submitter	clinical testing	Wong Mito Lab, Molecular and Human Genetics, Baylor College of Medicine	Oct 17, 2019	The NC_012920.1:m.11778G>A (YP_003024035.1:p.Arg340His) variant in MTND4 gene is interpretated to be a Pathogenic variant based on the modified ACMG guidelines (unpublished). This variant meets the following evidence codes: PS1, PS4 -

not provided Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen	Oct 23, 2020	- -
Pathogenic, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	May 12, 2017	m.11778G>A is one of a small number of primary variants which are causative of Leber hereditary optic neuropathy (LHON; MIM: 535000). It is estimated that 70% of LHON families of northern European descent carry the m.11778G>A variant (Mackey 1996). -
Pathogenic, criteria provided, single submitter	clinical testing	Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics	Nov 04, 2014	- -

not specified Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Institute for Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin

Sep 22, 2022

- -

Mitochondrial disease Pathogenic:1

Pathogenic, reviewed by expert panel

curation

ClinGen Mitochondrial Disease Nuclear and Mitochondrial Variant Curation Expert Panel, ClinGen

Jun 30, 2022

The m.11778G>A (p.R340H) variant in MT-ND4 has been reported in >16 unrelated individuals with primary mitochondrial disease. While this variant is one of the three most common variants associated with Leber Hereditary Optic Neuropathy (LHON; PMID: 20301353), affected individuals can also have other features. Indeed, affected individuals have been reported with features including LHON, Leigh syndrome, cerebellar ataxia, migraines, regression, leukoencephalopathy, myoclonus, psychiatric illness, Parkinsonism, axonal neuropathy, multiple sclerosis, and ophthalmoplegia; and this variant has been seen in affected individuals in the homoplasmic and heteroplasmic states (PS4; PMIDs: 3201231, 2575667, 2566021, 2390098, 1635296, 17724295, 18848389, 25917160, 18216301, 17254817, 8902729, 27119776). This variant segregated with disease in multiple affected members in multiple families and several healthy family members had lower to undetectable levels of the variant (PP1_moderate; PMIDs: 27119776, 2390098). There are no confirmed de novo occurrences of this variant to our knowledge. This variant is present in the healthy population, which is to be expected given the known reduced penetrance of this variant. The computational predictor APOGEE gives a consensus rating of pathogenic with a score of 0.97 (Min=0, Max=1), which predicts a damaging effect on gene function (PP3). Cybrid studies supported the functional impact of this variant (PS3_supporting; PMIDs: 10976107, 7763260). This variant meets criteria to be classified as likely pathogenic however this Expert Panel elected to modify the classification to pathogenic given the overwhelming evidence of pathogenicity. Furthermore, the mitochondrial DNA variant specifications are known to not be optimized for pathogenic variants that tend to be homoplasmic in nature and/or have reduced penetrance, such as the common variants associated with LHON. This classification was approved by the NICHD/NINDS U24 Mitochondrial Disease Variant Curation Expert Panel on May 24, 2022. Mitochondrial DNA-specific ACMG/AMP criteria applied (PMID: 32906214): PS3_supporting, PS4, PP1_moderate, PP3. -

Leber optic atrophy, susceptibility to Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

MGZ Medical Genetics Center

May 27, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
Apogee2	Pathogenic	0.93
Hmtvar	Pathogenic	0.85
AlphaMissense	Pathogenic	0.86
BayesDel_addAF	Benign	-0.29	T
DEOGEN2	Benign	0.24	T
LIST_S2	Uncertain	0.87	D
MutationAssessor	Pathogenic	5.1	H
MutationTaster	Benign	0.000055	A
PROVEAN	Pathogenic	-4.7	D
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
GERP RS		4.6
Varity_R		0.22

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs199476112; hg19: chrM-11779;