rs1450205264

Positions:

• chr1-12009680-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_014874.4(MFN2):​c.2158A>G​(p.Lys720Glu) variant causes a missense change. The variant allele was found at a frequency of 0.00000558 in 1,614,108 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K720I) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: MFN2 NM_014874.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.06

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 Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• 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.
• BP4: Computational evidence support a benign effect (MetaRNN=0.38522857).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MFN2	NM_014874.4	c.2158A>G	p.Lys720Glu	missense_variant	18/19	ENST00000235329.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MFN2	ENST00000235329.10	c.2158A>G	p.Lys720Glu	missense_variant	18/19	1	NM_014874.4	P1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152216 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461892 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 727248

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000360

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152216 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74372

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Charcot-Marie-Tooth disease type 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 14, 2023

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. 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. ClinVar contains an entry for this variant (Variation ID: 543247). This variant has not been reported in the literature in individuals affected with MFN2-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.007%). This sequence change replaces lysine, which is basic and polar, with glutamic acid, which is acidic and polar, at codon 720 of the MFN2 protein (p.Lys720Glu). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.19
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.35
CADD	Benign	20
DANN	Benign	0.79
DEOGEN2	Benign	0.30	T;T
Eigen	Benign	-0.31
Eigen_PC	Benign	-0.032
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Benign	0.79	T;.
M_CAP	Uncertain	0.20	D
MetaRNN	Benign	0.39	T;T
MetaSVM	Uncertain	-0.075	T
MutationAssessor	Benign	-0.10	N;N
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.64	T
PROVEAN	Benign	1.0	N;N
REVEL	Uncertain	0.58
Sift	Benign	1.0	T;T
Sift4G	Benign	1.0	T;T
Polyphen		0.0040	B;B
Vest4		0.53
MutPred		0.49		Loss of ubiquitination at K720 (P = 0.011);Loss of ubiquitination at K720 (P = 0.011);
MVP		0.98
MPC		0.94
ClinPred		0.80	D
GERP RS		5.3
Varity_R		0.25
gMVP		0.62

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

LitVar

Other links and lift over

dbSNP: rs1450205264; hg19: chr1-12069737;