rs199476118

Positions:

• chrM-3460-G-A

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PS3_Moderate PP3 PM6_Supporting PS4 PP1_Moderate

This summary comes from the ClinGen Evidence Repository: The m.3460G>A (p.A52T) variant in MT-ND1 has been reported in affected individuals from more than 50 kindreds (PS4, PMIDs: 1928099, 1674640, 7629530, 1734726, 1550131, 8496715, 8024249, 8556281, 8571959, 12205655, 11906302, 12807863, 12518276, 16738010, 17122117, 18216301, 18562849, 20232220, 21887510, 25338955, 25053773, 28314831, 30053855, 30591017). 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, several individuals have been reported with multiple sclerosis. Other features have been variably seen in affected individuals including sensorineural hearing loss, auditory neuropathy, epilepsy, migraines, Parkinsonism, dystonia, Leigh syndrome, spinal cord lesions, myoclonus, myopathy, hypertension, high triglycerides, diabetes, and cardiac involvement. Testing excluding separate etiologies for these features has been limited. Heteroplasmy levels in affected individuals ranged from 58% to homoplasmy. Age of onset varied from four years old to 75 years old. 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: 1734726, 8571959, 11906302). There is one reported de novo occurrence to our knowledge (PM6_supporting; PMID:12518276). 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 0.86 (Min=0, Max=1), which predicts a damaging effect on gene function (PP3). Extensive cybrid studies supported the functional impact of this variant, as do E. coli and mouse studies (PS3_moderate PMIDs: 35383288, 22079202, 15720387, 15883259, 15342361, 10976107). In summary, this variant meets criteria to be classified as pathogenic for primary mitochondrial disease inherited in a mitochondrial manner. This classification was approved by the NICHD/NINDS U24 ClinGen Mitochondrial Disease Variant Curation Expert Panel on April 25, 2023. Mitochondrial DNA-specific ACMG/AMP criteria applied (PMID:32906214): PS4, PP1_moderate, PM6_supporting, PP3, PS3_moderate. LINK:https://erepo.genome.network/evrepo/ui/classification/CV9722/MONDO:0044970/014

• Frequency: Mitomap GenBank: Absent
• Consequence: MT-ND1 ENST00000361390.2 missense
• Scores: Apogee2 Pathogenic 0.87
• Clinical Significance: Pathogenic reviewed by expert panel P:8 O:2 LHON
• Conservation: PhyloP100: 6.38

Genes affected

MT-ND1 (HGNC:7455): (mitochondrially encoded NADH dehydrogenase 1) Enables NADH dehydrogenase (ubiquinone) activity. Involved in mitochondrial electron transport, NADH to ubiquinone and mitochondrial respiratory chain complex I assembly. Located in mitochondrial membrane. Part of mitochondrial respiratory chain complex I. Implicated in several diseases, including MELAS syndrome; neurodegenerative disease (multiple); optic nerve disease (multiple); toxic shock syndrome; and type 2 diabetes mellitus. Biomarker of Alzheimer's disease; Parkinson's disease; and multiple sclerosis. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Pathogenic. Variant got 10 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-ND1	ENST00000361390.2	c.154G>A	p.Ala52Thr	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: 0.0 AC: 0 AN: 56426

Gnomad heteroplasmic AF: 0.000018 AC: 1 AN: 56426

Mitomap

LHON

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:8 Other:2

Revision: reviewed by expert panel

Submissions by phenotype

Leber optic atrophy Pathogenic:4 Other:1

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	Wong Mito Lab, Molecular and Human Genetics, Baylor College of Medicine	Oct 17, 2019	The NC_012920.1:m.3460G>A (YP_003024026.1:p.Ala52Thr) variant in MTND1 gene is interpretated to be a Pathogenic variant based on the modified ACMG guidelines (unpublished). This variant meets the following evidence codes: PS1, PS3 -
Pathogenic, no assertion criteria provided	literature only	OMIM	Jul 10, 2007	- -
Pathogenic, no assertion criteria provided	clinical testing	Genomics England Pilot Project, Genomics England	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Mendelics	May 04, 2022	- -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Nov 22, 2017	m.3460G>A is one of a small number of primary variants which are causative of Leber hereditary optic neuropathy (LHON; MIM: 535000; Howell 1992). It is estimated that 15%-25% of LHON families carry the g.3460G>A variant (Howell 1991). -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen	Oct 23, 2020	- -

Mitochondrial disease Pathogenic:1

Pathogenic, reviewed by expert panel

curation

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

Apr 25, 2023

The m.3460G>A (p.A52T) variant in MT-ND1 has been reported in affected individuals from more than 50 kindreds (PS4, PMIDs: 1928099, 1674640, 7629530, 1734726, 1550131, 8496715, 8024249, 8556281, 8571959, 12205655, 11906302, 12807863, 12518276, 16738010, 17122117, 18216301, 18562849, 20232220, 21887510, 25338955, 25053773, 28314831, 30053855, 30591017). 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, several individuals have been reported with multiple sclerosis. Other features have been variably seen in affected individuals including sensorineural hearing loss, auditory neuropathy, epilepsy, migraines, Parkinsonism, dystonia, Leigh syndrome, spinal cord lesions, myoclonus, myopathy, hypertension, high triglycerides, diabetes, and cardiac involvement. Testing excluding separate etiologies for these features has been limited. Heteroplasmy levels in affected individuals ranged from 58% to homoplasmy. Age of onset varied from four years old to 75 years old. 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: 1734726, 8571959, 11906302). There is one reported de novo occurrence to our knowledge (PM6_supporting; PMID: 12518276). 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 0.86 (Min=0, Max=1), which predicts a damaging effect on gene function (PP3). Extensive cybrid studies supported the functional impact of this variant, as do E. coli and mouse studies (PS3_moderate PMIDs: 35383288, 22079202, 15720387, 15883259, 15342361, 10976107). In summary, this variant meets criteria to be classified as pathogenic for primary mitochondrial disease inherited in a mitochondrial manner. This classification was approved by the NICHD/NINDS U24 ClinGen Mitochondrial Disease Variant Curation Expert Panel on April 25, 2023. Mitochondrial DNA-specific ACMG/AMP criteria applied (PMID: 32906214): PS4, PP1_moderate, PM6_supporting, PP3, PS3_moderate. -

MITOCHONDRIAL COMPLEX I DEFICIENCY, MITOCHONDRIAL TYPE 3 Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Jul 10, 2007

- -

Leigh syndrome Other:1

not provided, no classification provided

literature only

GeneReviews

-

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
Apogee2	Pathogenic	0.87
Hmtvar	Pathogenic	0.76
AlphaMissense	Pathogenic	0.62
BayesDel_addAF	Uncertain	0.13	D
DEOGEN2	Benign	0.13	T
LIST_S2	Benign	0.80	T
MutationAssessor	Uncertain	2.8	M
MutationTaster	Benign	4.2e-11	A
PROVEAN	Uncertain	-2.4	N
Sift4G	Pathogenic	0.0010	D
GERP RS		4.8
Varity_R		0.63

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs199476118; hg19: chrM-3461; COSMIC: COSV62293268; COSMIC: COSV62293268;