rs119103263

Positions:

• chr1-11992659-C-G
• chr1-11992659-C-T

Variant summary

Our verdict is Pathogenic. Variant got 17 ACMG points: 17P and 0B. PM1 PM2 PM5 PP2 PP3_Moderate PP5_Very_Strong

The NM_014874.4(MFN2):​c.280C>G​(p.Arg94Gly) variant causes a missense 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. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R94Q) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 31)
• Consequence: MFN2 NM_014874.4 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2 U:1
• Conservation: PhyloP100: 3.14

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]

ACMG classification

Verdict is Pathogenic. Variant got 17 ACMG points.

• PM1: In a domain Dynamin-type G (size 249) in uniprot entity MFN2_HUMAN there are 66 pathogenic changes around while only 3 benign (96%) 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 chr1-11992660-G-A is described in Lovd as [Pathogenic].
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), MFN2. . Gene score misZ 1.6575 (greater than the threshold 3.09). Trascript score misZ 3.2174 (greater than threshold 3.09). GenCC has associacion of gene with Charcot-Marie-Tooth disease type 2A2, axonal hereditary motor and sensory neuropathy, hereditary motor and sensory neuropathy type 6, Charcot-Marie-Tooth disease, axonal, autosomal recessive, type 2a2b;, multiple symmetric lipomatosis, severe early-onset axonal neuropathy due to MFN2 deficiency.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.886
• PP5: Variant 1-11992659-C-G is Pathogenic according to our data. Variant chr1-11992659-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 637495.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MFN2	NM_014874.4	c.280C>G	p.Arg94Gly	missense_variant	4/19	ENST00000235329.10	NP_055689.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MFN2	ENST00000235329.10	c.280C>G	p.Arg94Gly	missense_variant	4/19	1	NM_014874.4	ENSP00000235329	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2 Uncertain:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Charcot-Marie-Tooth disease type 2 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 03, 2023

This sequence change replaces arginine, which is basic and polar, with glycine, which is neutral and non-polar, at codon 94 of the MFN2 protein (p.Arg94Gly). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with autosomal dominant Charcot-Marie-Tooth disease (PMID: 21508331). ClinVar contains an entry for this variant (Variation ID: 637495). 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 expected to disrupt MFN2 protein function with a positive predictive value of 95%. This variant disrupts the p.Arg94 amino acid residue in MFN2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 15064763, 16437557, 16714318, 17215403, 20418531, 24862862). 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. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

CeGaT Center for Human Genetics Tuebingen

Jun 01, 2018

- -

Charcot-Marie-Tooth disease Uncertain:1

Uncertain significance, no assertion criteria provided

literature only

Inherited Neuropathy Consortium

-

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.50
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.73	D;D;.
Eigen	Uncertain	0.53
Eigen_PC	Uncertain	0.46
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Pathogenic	0.97	D;.;D
M_CAP	Pathogenic	0.47	D
MetaRNN	Pathogenic	0.89	D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.8	M;M;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Pathogenic	-6.3	D;D;D
REVEL	Pathogenic	0.87
Sift	Pathogenic	0.0	D;D;D
Sift4G	Uncertain	0.0030	D;D;D
Polyphen		1.0	D;D;.
Vest4		0.88
MutPred		0.60		Loss of MoRF binding (P = 0.0325);Loss of MoRF binding (P = 0.0325);Loss of MoRF binding (P = 0.0325);
MVP		0.98
MPC		2.0
ClinPred		0.99	D
GERP RS		3.6
Varity_R		0.93
gMVP		0.93

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs119103263; hg19: chr1-12052716;