NM_000268.4:c.1550T>C

Variant names:

• chr22-29678299-T-C
• rs1556002568
• NM_000268.4:c.1550T>C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PP3_Moderate PP5

The NM_000268.4(NF2):​c.1550T>C​(p.Leu517Pro) variant causes a missense change. 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 Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: NF2 NM_000268.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4 U:1
• Conservation: PhyloP100: 6.21

Genes affected

NF2 (HGNC:7773): (NF2, moesin-ezrin-radixin like (MERLIN) tumor suppressor) This gene encodes a protein that is similar to some members of the ERM (ezrin, radixin, moesin) family of proteins that link cytoskeletal components with proteins in the cell membrane. The encoded protein is involved in regulation of contact-dependent inhibition of cell proliferation and functions in cell-cell adhesion and transmembrane signaling. The encoded protein has been shown to interact with cell-surface proteins, proteins involved in cytoskeletal dynamics, and proteins involved in regulating ion transport. Disruption of this protein's function has been implicated in tumorigenesis and metastasis. Mutations in this gene are associated with neurofibromatosis type II which is characterized by nervous system and skin tumors and ocular abnormalities. [provided by RefSeq, May 2022]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.869
• PP5: Variant 22-29678299-T-C is Pathogenic according to our data. Variant chr22-29678299-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 547709.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=3, Uncertain_significance=1, Pathogenic=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF2	NM_000268.4	c.1550T>C	p.Leu517Pro	missense_variant	Exon 14 of 16	ENST00000338641.10	NP_000259.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF2	ENST00000338641.10	c.1550T>C	p.Leu517Pro	missense_variant	Exon 14 of 16	1	NM_000268.4	ENSP00000344666.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:4 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Neurofibromatosis, type 2 Pathogenic:2 Uncertain:1

Jan 13, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 517 of the NF2 protein (p.Leu517Pro). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with NF2-related conditions. ClinVar contains an entry for this variant (Variation ID: 547709). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on NF2 protein function. Experimental studies have shown that this missense change affects NF2 function (PMID: 26045165). 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. -

Nov 07, 2021

Genome-Nilou Lab

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Nov 01, 2016

Center for Human Genetics, Inc, Center for Human Genetics, Inc

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Pathogenic:1

Dec 16, 2019

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Published functional studies demonstrate a damaging effect: fails to bind Lats1 and results in decreased phosphor-YAP (Li et al., 2015); Not observed in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; This variant is associated with the following publications: (PMID: 16983642, 26045165) -

Hereditary cancer-predisposing syndrome Pathogenic:1

Jan 27, 2019

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.L517P variant (also known as c.1550T>C), located in coding exon 14 of the NF2 gene, results from a T to C substitution at nucleotide position 1550. The leucine at codon 517 is replaced by proline, an amino acid with similar properties. This alteration was seen in a patient with bilateral vestibular schwannomas (Ahronowitz I et al. Hum. Mutat., 2007 Jan;28:1-12). This variant was not reported in population-based cohorts in the Genome Aggregation Database (gnomAD). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.44	D
BayesDel_noAF	Pathogenic	0.40
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.86	D;.;.;.;.;.;.;.;.
Eigen	Uncertain	0.37
Eigen_PC	Uncertain	0.47
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.99	D;D;D;.;.;D;.;D;D
M_CAP	Pathogenic	0.34	D
MetaRNN	Pathogenic	0.87	D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.44	D
MutationAssessor	Uncertain	2.2	M;.;.;M;.;.;M;.;M
PrimateAI	Pathogenic	0.92	D
PROVEAN	Uncertain	-4.3	D;D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.85
Sift	Uncertain	0.0010	D;D;D;D;D;D;D;D;D
Sift4G	Benign	0.073	T;T;T;T;T;T;T;D;T
Polyphen		0.38	B;P;B;B;B;B;B;B;B
Vest4		0.76
MutPred		0.76		Loss of stability (P = 0.0311);.;.;Loss of stability (P = 0.0311);.;.;Loss of stability (P = 0.0311);.;Loss of stability (P = 0.0311);
MVP		0.99
MPC		1.7
ClinPred		0.99	D
GERP RS		5.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.7
Varity_R		0.93
gMVP		0.78

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: rs1556002568; hg19: chr22-30074288;