22-29674946-G-T

Variant names:

• chr22-29674946-G-T
• rs367829184
• NM_000268.4:c.1446+5G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_000268.4(NF2):​c.1446+5G>T variant causes a splice region, intron change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: NF2 NM_000268.4 splice_region, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.28
• Publications: 0 publications found

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]

NF2 Gene-Disease associations (from GenCC):

• NF2-related schwannomatosis

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, ClinGen, Orphanet, Labcorp Genetics (formerly Invitae), G2P
• familial meningioma

  Inheritance: Unknown Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF2	NM_000268.4	c.1446+5G>T		splice_region_variant, intron_variant	Intron 13 of 15	ENST00000338641.10	NP_000259.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF2	ENST00000338641.10	c.1446+5G>T		splice_region_variant, intron_variant	Intron 13 of 15	1	NM_000268.4	ENSP00000344666.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1404994 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 693588

African (AFR) AF: 0.00 AC: 0 AN: 31934

American (AMR) AF: 0.00 AC: 0 AN: 36634

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25230

East Asian (EAS) AF: 0.00 AC: 0 AN: 36462

South Asian (SAS) AF: 0.00 AC: 0 AN: 79586

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 49682

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5674

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1081556

Other (OTH) AF: 0.00 AC: 0 AN: 58236

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neurofibromatosis, type 2 Uncertain:1

Mar 06, 2019

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change falls in intron 13 of the NF2 gene. It does not directly change the encoded amino acid sequence of the NF2 protein, but it affects a nucleotide within the consensus splice site of the intron. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with NF2-related conditions. Nucleotide substitutions within the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site, but this prediction has not been confirmed by published transcriptional studies. 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.

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.20
CADD	Pathogenic	35
DANN	Uncertain	0.97
PhyloP100		4.3

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.99
SpliceAI score (max)		0.84		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.84		Position offset: 35
DS_DL_spliceai		0.40		Position offset: -5

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

Other links and lift over

dbSNP: rs367829184; hg19: chr22-30070935;