Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_ModeratePM2PP5_Moderate
The NM_014874.4(MFN2):c.2256C>G(p.Tyr752*) variant causes a stop gained 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 (★). Synonymous variant affecting the same amino acid position (i.e. Y752Y) has been classified as Likely benign.
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;
Our verdict: Likely_pathogenic. The variant received 6 ACMG points.
PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.00792 CDS is truncated, and there are 3 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 1-12011547-C-G is Pathogenic according to our data. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-12011547-C-G is described in CliVar as Pathogenic. Clinvar id is 240946.Status of the report is criteria_provided_single_submitter, 1 stars.
This sequence change results in a premature translational stop signal in the last exon of the MFN2 mRNA at codon 752 (p.Tyr752*). While this is not anticipated to result in nonsense mediated decay, it is expected to create a truncated MFN2 protein. This variant is not present in population databases (ExAC no frequency). While this particular nucleotide change has not been reported in the literature, a different nucleotide change c.2256C>A causing the same p.Tyr752* truncation has been reported in a patient affected with CMT2A (PMID: 21508331). This variant is expected to interfere with MFN2 protein function because it disrupts a highly conserved coiled-coil region which is essential for tethering of mitochondria before fusion (PMID: 21508331). In summary, this sequence change is predicted to produce a truncated protein product which disrupts a highly conserved functional region of the MFN2 protein. While this variant is novel at the nucleotide level, the same protein truncation has been reported in a patient affected with CMT2A. For these reasons, it has been classified as Pathogenic. -