rs119103268

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1PM2PM5PP2PP3_StrongPP5_Very_Strong

The NM_014874.4(MFN2):​c.310C>T​(p.Arg104Trp) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R104L) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 31)

Consequence

MFN2
NM_014874.4 missense, splice_region

Scores

13
5
1
Splicing: ADA: 0.03669
2

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:19

Conservation

PhyloP100: 3.54

Publications

33 publications found
Variant links:
Genes affected
MFN2 (HGNC:16877): (mitofusin 2) This gene encodes a mitochondrial membrane protein that participates in mitochondrial fusion and contributes to the maintenance and operation of the mitochondrial network. This protein is involved in the regulation of vascular smooth muscle cell proliferation, and it may play a role in the pathophysiology of obesity. Mutations in this gene cause Charcot-Marie-Tooth disease type 2A2, and hereditary motor and sensory neuropathy VI, which are both disorders of the peripheral nervous system. Defects in this gene have also been associated with early-onset stroke. Two transcript variants encoding the same protein have been identified. [provided by RefSeq, Jul 2008]
MFN2 Gene-Disease associations (from GenCC):
  • neuropathy, hereditary motor and sensory, type 6A
    Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
  • Charcot-Marie-Tooth disease, axonal, autosomal recessive, type 2a2b;
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
  • axonal hereditary motor and sensory neuropathy
    Inheritance: SD Classification: DEFINITIVE Submitted by: ClinGen
  • Charcot-Marie-Tooth disease type 2A2
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)
  • hereditary motor and sensory neuropathy type 6
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • multiple symmetric lipomatosis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • severe early-onset axonal neuropathy due to MFN2 deficiency
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 19 ACMG points.

PM1
In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 10 uncertain in NM_014874.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-11992690-G-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 214651.
PP2
Missense variant in the MFN2 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 123 curated pathogenic missense variants (we use a threshold of 10). The gene has 23 curated benign missense variants. Gene score misZ: 1.6575 (below the threshold of 3.09). Trascript score misZ: 3.2174 (above the threshold of 3.09). GenCC associations: The gene is linked to Charcot-Marie-Tooth disease type 2A2, Charcot-Marie-Tooth disease, axonal, autosomal recessive, type 2a2b;, severe early-onset axonal neuropathy due to MFN2 deficiency, hereditary motor and sensory neuropathy type 6, axonal hereditary motor and sensory neuropathy, multiple symmetric lipomatosis, neuropathy, hereditary motor and sensory, type 6A.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.982
PP5
Variant 1-11992689-C-T is Pathogenic according to our data. Variant chr1-11992689-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 2281.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MFN2NM_014874.4 linkc.310C>T p.Arg104Trp missense_variant, splice_region_variant Exon 4 of 19 ENST00000235329.10 NP_055689.1 O95140-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MFN2ENST00000235329.10 linkc.310C>T p.Arg104Trp missense_variant, splice_region_variant Exon 4 of 19 1 NM_014874.4 ENSP00000235329.5 O95140-1

Frequencies

GnomAD3 genomes
Cov.:
31
GnomAD4 exome
Cov.:
31
GnomAD4 genome
Cov.:
31

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:19
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Charcot-Marie-Tooth disease type 2A2 Pathogenic:8
Apr 25, 2018
Institute of Human Genetics, Cologne University
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Jul 20, 2021
Laboratório de Neurologia Aplicada e Experimental, Faculdade de Medicina de Ribeirao Preto – Universidade de Sao Paulo
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

- -

Jun 26, 2025
Neurogenetics and Molecular Medicine Laboratory, Institut De Recerca Sant Joan De Déu
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.310C>T variant (NM_001127660.1) in MFN2 is a missense variant predicted to cause an amino acid change of Arg by Trp at position 104 in the protein sequence (p.(Arg104Trp)). This variant is absent from population databases (gnomAD v2.1; PM2_supporting). This variant has been identified as de novo in an individual with Charcot-Marie-Tooth disease, axonal, type 2A2A (PMID: 35177962; internal lab contributor; PS2). The variant cosegregates with the disease in multiple affected family members in a gene definitively known to cause the disease and it is related to several articles (ClinVar Variation ID: 2281; PMIDs: 18425620, 18946002, 18957892, 20008656, 21531138, 21840889, 25025039; PP1_verystrong). The computational predictor REVEL and CADD unanimously support a deleterious effect of the variant (REVEL score: 0.981; CADD score 27.7; PP3_moderate). This variant resides within a region of MFN2 that is defined as a exonic mutational hotspot (PM1). Functional studies performed in patient's fibroblasts conducted at the Neurogenetics and Molecular Medicine Laboratory showed aberrant protein function, mitochondrial morphology defects, and decreased mitochondria–lysosome contacts (PMID: 35177962; PS3). In summary, this variant meets the criteria to be classified as Pathogenic based on the ACMG/AMP criteria applied. -

Dec 01, 2020
CMT Laboratory, Bogazici University
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 13, 2023
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 23, 2023
3billion
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The variant is not observed in the gnomAD v2.1.1 dataset. Missense changes are a common disease-causing mechanism. In silico tool predictions suggest damaging effect of the variant on gene or gene product (REVEL: 0.93; 3Cnet: 1.00). Same nucleotide change resulting in same amino acid change has been previously reported as pathogenic/likely pathogenic with strong evidence (ClinVar ID: VCV000002281). Different missense changes at the same codon (p.Arg104Gln, p.Arg104Leu) have been reported as pathogenic/likely pathogenic with strong evidence (ClinVar ID: VCV000214651, VCV000637289). Therefore, this variant is classified as Pathogenic according to the recommendation of ACMG/AMP guideline. -

Dec 09, 2008
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Apr 30, 2024
Department of Clinical Genetics, Copenhagen University Hospital, Rigshospitalet
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

PP5_VStr, PP3_Sup, PM2_Sup, PP2_Sup -

Charcot-Marie-Tooth disease Pathogenic:2
-
Molecular Genetics Laboratory, London Health Sciences Centre
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 01, 2013
Dept. of Medical Genetics, Telemark Hospital Trust, Telemark Hospital Trust
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:research

- -

Hereditary motor and sensory neuropathy with optic atrophy Pathogenic:2
Dec 09, 2008
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Sep 04, 2019
Centre for Mendelian Genomics, University Medical Centre Ljubljana
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was classified as: Pathogenic. The following ACMG criteria were applied in classifying this variant: PS1,PM1,PM2,PM5,PP3. -

not provided Pathogenic:2
Apr 14, 2022
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 18425620, 26307494, 25025039, 30442897, 21840889, 21531138, 18946002, 30340945, 33851411, 34169998, 24863639) -

Mar 01, 2017
Eurofins Ntd Llc (ga)
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Hereditary motor and sensory neuropathy with optic atrophy;C4310725:Charcot-Marie-Tooth disease, axonal, autosomal recessive, type 2a2b;;C4721887:Charcot-Marie-Tooth disease type 2A2 Pathogenic:1
May 18, 2017
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Pathogenic:1
Apr 06, 2021
Ambry Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R104W pathogenic mutation (also known as c.310C>T), located in coding exon 2 of the MFN2 gene, results from a C to T substitution at nucleotide position 310. The arginine at codon 104 is replaced by tryptophan, an amino acid with dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. The p.R104W alteration has been reported in multiple patients with Charcot-Marie-Tooth disease (Brockmann K et al. J Neurol, 2008 Jul;255(7):1049-58; Baets J et al. Brain, 2011 Sep;134:2664-76; Genari AB et al. Neuromuscul Disord, 2011 Jun;21:428-32; Høyer H et al. Biomed Res Int, 2014 Jun;2014:210401). Another alteration at the same codon, p.R104Q (c.311G>A), has been described in a patient with Charcot-Marie-Tooth (Bombelli F et al. JAMA Neurol, 2014 Aug;71:1036-42). The p.R104W amino acid is located in the GTPase domain which is required for mitochondrial membrane fusion reaction, and multiple alterations in this region have been reported (Amiott EA et al. Exp Neurol, 2008 May;211:115-27; Ando M et al. J Peripher Nerv Syst, 2017 09;22:191-199). Based on the supporting evidence, this variant is expected to be causative of autosomal dominant Charcot-Marie-Tooth disease (CMT) type 2A2A and hereditary motor and sensory neuropathy VIA; however, its clinical significance for autosomal recessive Charcot-Marie-Tooth disease (CMT) type 2A2B is unclear. -

Charcot-Marie-Tooth disease, axonal, autosomal recessive, type 2a2b; Pathogenic:1
Mar 13, 2023
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Charcot-Marie-Tooth disease type 2 Pathogenic:1
Nov 11, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 104 of the MFN2 protein (p.Arg104Trp). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with Charcot-Marie-Tooth disease (PMID: 18425620, 18946002, 18957892, 20008656, 21531138, 21840889, 25025039). In at least one individual the variant was observed to be de novo. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 2281). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt MFN2 protein function with a positive predictive value of 95%. This variant disrupts the p.Arg104 amino acid residue in MFN2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 22492563). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Neuropathy, hereditary motor and sensory, type 6A Pathogenic:1
Mar 13, 2023
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.97
BayesDel_addAF
Pathogenic
0.54
D
BayesDel_noAF
Pathogenic
0.54
CADD
Pathogenic
28
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.96
D;D
Eigen
Uncertain
0.52
Eigen_PC
Uncertain
0.41
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.97
D;.
M_CAP
Pathogenic
0.52
D
MetaRNN
Pathogenic
0.98
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.5
H;H
PhyloP100
3.5
PrimateAI
Pathogenic
0.89
D
PROVEAN
Pathogenic
-7.4
D;D
REVEL
Pathogenic
0.93
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0010
D;D
Polyphen
1.0
D;D
Vest4
0.95
MutPred
0.85
Loss of disorder (P = 0.0255);Loss of disorder (P = 0.0255);
MVP
0.98
MPC
1.8
ClinPred
1.0
D
GERP RS
2.2
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
2.7
Varity_R
0.95
gMVP
0.94
Mutation Taster
=1/99
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.037
dbscSNV1_RF
Benign
0.27
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs119103268; hg19: chr1-12052746; API