4-119136579-C-CA

Variant names:

• chr4-119136579-C-CA
• rs1175205512
• NM_016599.5:c.55dupA

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The NM_016599.5(MYOZ2):​c.55dupA​(p.Met19AsnfsTer8) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: MYOZ2 NM_016599.5 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.18

Genes affected

MYOZ2 (HGNC:1330): (myozenin 2) The protein encoded by this gene belongs to a family of sarcomeric proteins that bind to calcineurin, a phosphatase involved in calcium-dependent signal transduction in diverse cell types. These family members tether calcineurin to alpha-actinin at the z-line of the sarcomere of cardiac and skeletal muscle cells, and thus they are important for calcineurin signaling. Mutations in this gene cause cardiomyopathy familial hypertrophic type 16, a hereditary heart disorder. [provided by RefSeq, Aug 2011]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 5 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYOZ2	NM_016599.5	c.55dupA	p.Met19AsnfsTer8	frameshift_variant	Exon 2 of 6	ENST00000307128.6	NP_057683.1
MYOZ2	XM_006714234.5	c.55dupA	p.Met19AsnfsTer8	frameshift_variant	Exon 2 of 6		XP_006714297.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYOZ2	ENST00000307128.6	c.55dupA	p.Met19AsnfsTer8	frameshift_variant	Exon 2 of 6	1	NM_016599.5	ENSP00000306997.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hypertrophic cardiomyopathy Uncertain:1

Aug 03, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Met19Asnfs*8) in the MYOZ2 gene. It is expected to result in an absent or disrupted protein product. However, the current clinical and genetic evidence is not sufficient to establish whether loss-of-function variants in MYOZ2 cause disease. 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. This variant has not been reported in the literature in individuals affected with MYOZ2-related conditions. This variant is not present in population databases (gnomAD no frequency). -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.090		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: rs1175205512; hg19: chr4-120057734;