rs749606728

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 1P and 4B. PP2BP4_Strong

The NM_014874.4(MFN2):​c.1729A>G​(p.Ile577Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000434 in 1,614,030 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. I577I) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000041 ( 0 hom. )

Consequence

MFN2
NM_014874.4 missense

Scores

1
18

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: -1.99

Publications

0 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: Likely_benign. The variant received -3 ACMG points.

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.
BP4
Computational evidence support a benign effect (MetaRNN=0.03580439).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MFN2NM_014874.4 linkc.1729A>G p.Ile577Val missense_variant Exon 16 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.1729A>G p.Ile577Val missense_variant Exon 16 of 19 1 NM_014874.4 ENSP00000235329.5 O95140-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152162
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000796
AC:
2
AN:
251396
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000410
AC:
6
AN:
1461868
Hom.:
0
Cov.:
33
AF XY:
0.00000275
AC XY:
2
AN XY:
727234
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53394
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000540
AC:
6
AN:
1112012
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152162
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74350
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41436
American (AMR)
AF:
0.00
AC:
0
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68016
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000434
Hom.:
0
Bravo
AF:
0.0000113
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
Apr 09, 2025
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis indicates that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Oct 09, 2019
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The MFN2 c.1729A>G; p.Ile577Val variant (rs749606728), to our knowledge, is not reported in the medical literature but is reported in ClinVar (Variation ID: 246602). This variant is found on only two chromosomes (2/113698 alleles) in the Genome Aggregation Database. The isoleucine at codon 577 is weakly conserved, and computational analyses (SIFT, PolyPhen-2) predict that this variant is tolerated. However, due to limited information, the clinical significance of the p.Ile577Val variant is uncertain at this time. -

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

This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 577 of the MFN2 protein (p.Ile577Val). This variant is present in population databases (rs749606728, gnomAD 0.002%). This variant has not been reported in the literature in individuals affected with MFN2-related conditions. ClinVar contains an entry for this variant (Variation ID: 246602). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt MFN2 protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.061
BayesDel_addAF
Benign
-0.095
T
BayesDel_noAF
Benign
-0.36
CADD
Benign
0.31
DANN
Benign
0.28
DEOGEN2
Benign
0.12
T;T
Eigen
Benign
-1.4
Eigen_PC
Benign
-1.5
FATHMM_MKL
Benign
0.11
N
LIST_S2
Benign
0.60
T;.
M_CAP
Benign
0.020
T
MetaRNN
Benign
0.036
T;T
MetaSVM
Uncertain
0.64
D
MutationAssessor
Benign
0.34
N;N
PhyloP100
-2.0
PrimateAI
Benign
0.25
T
PROVEAN
Benign
-0.080
N;N
REVEL
Benign
0.20
Sift
Benign
0.68
T;T
Sift4G
Benign
0.50
T;T
Polyphen
0.0
B;B
Vest4
0.15
MutPred
0.23
Gain of disorder (P = 0.0705);Gain of disorder (P = 0.0705);
MVP
0.35
MPC
0.17
ClinPred
0.0077
T
GERP RS
-3.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.036
gMVP
0.12
Mutation Taster
=93/7
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
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: rs749606728; hg19: chr1-12066607; API