1-11996248-G-T

Variant names:

• chr1-11996248-G-T
• NM_014874.4:c.404G>T

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP3_Moderate

The NM_014874.4(MFN2):​c.404G>T​(p.Arg135Leu) variant causes a missense change involving the alteration of a 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 Uncertain significance (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R135Q) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MFN2 NM_014874.4 missense
• Clinical Significance: Uncertain significance no assertion criteria provided U:1
• Conservation: PhyloP100: 9.58

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 Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in NM_014874.4
• PM2: Very rare variant in population databases, with high coverage
• 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, 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, 0.854

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MFN2	NM_014874.4	c.404G>T	p.Arg135Leu	missense_variant	Exon 5 of 19	ENST00000235329.10	NP_055689.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MFN2	ENST00000235329.10	c.404G>T	p.Arg135Leu	missense_variant	Exon 5 of 19	1	NM_014874.4	ENSP00000235329.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: no assertion criteria provided

Submissions by phenotype

Neuropathy, hereditary motor and sensory, type 6A Uncertain:1

Nov 02, 2021

Clinical Genetics Laboratory, University Hospital Schleswig-Holstein

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.34
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.46
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.84	D;D
Eigen	Uncertain	0.51
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.97	D;.
M_CAP	Uncertain	0.099	D
MetaRNN	Pathogenic	0.85	D;D
MetaSVM	Uncertain	0.62	D
MutationAssessor	Benign	-0.26	N;N
PrimateAI	Pathogenic	0.89	D
PROVEAN	Benign	-2.3	N;N
REVEL	Pathogenic	0.76
Sift	Benign	0.045	D;D
Sift4G	Benign	0.12	T;T
Polyphen		0.83	P;P
Vest4		0.84
MutPred		0.53		Gain of sheet (P = 0.0221);Gain of sheet (P = 0.0221);
MVP		0.99
MPC		1.3
ClinPred		0.86	D
GERP RS		5.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.68
gMVP		0.96

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr1-12056305; COSMIC: COSV105862076; COSMIC: COSV105862076;