NM_152263.4:c.855delA

Variant names:

• chr1-154167939-AT-A
• rs199474719
• NM_152263.4:c.855delA

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PVS1_Moderate PM2 PP5

The NM_152263.4(TPM3):​c.855delA​(p.Ter286AsnfsTer74) variant causes a frameshift, splice region change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: TPM3 NM_152263.4 frameshift, splice_region
• Clinical Significance: Pathogenic no assertion criteria provided P:1 O:1
• Conservation: PhyloP100: 3.66
• Publications: 2 publications found

Genes affected

TPM3 (HGNC:12012): (tropomyosin 3) This gene encodes a member of the tropomyosin family of actin-binding proteins. Tropomyosins are dimers of coiled-coil proteins that provide stability to actin filaments and regulate access of other actin-binding proteins. Mutations in this gene result in autosomal dominant nemaline myopathy and other muscle disorders. This locus is involved in translocations with other loci, including anaplastic lymphoma receptor tyrosine kinase (ALK) and neurotrophic tyrosine kinase receptor type 1 (NTRK1), which result in the formation of fusion proteins that act as oncogenes. There are numerous pseudogenes for this gene on different chromosomes. Alternative splicing results in multiple transcript variants. [provided by RefSeq, May 2013]

TPM3 Gene-Disease associations (from GenCC):

• congenital myopathy 4A, autosomal dominant

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• TPM3-related myopathy

  Inheritance: SD Classification: DEFINITIVE Submitted by: ClinGen
• congenital myopathy 4B, autosomal recessive

  Inheritance: SD, AR Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• congenital fiber-type disproportion myopathy

  Inheritance: SD, AD Classification: MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet
• cap myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• childhood-onset nemaline myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• congenital generalized hypercontractile muscle stiffness syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• intermediate nemaline myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 5 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 0.0035 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 1-154167939-AT-A is Pathogenic according to our data. Variant chr1-154167939-AT-A is described in ClinVar as Pathogenic. ClinVar VariationId is 12451.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TPM3	NM_152263.4	c.855delA	p.Ter286AsnfsTer74	frameshift_variant, splice_region_variant	Exon 10 of 10	ENST00000651641.1	NP_689476.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TPM3	ENST00000651641.1	c.855delA	p.Ter286AsnfsTer74	frameshift_variant, splice_region_variant	Exon 10 of 10		NM_152263.4	ENSP00000498577.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1 Other:1

Revision: no assertion criteria provided

Submissions by phenotype

Congenital myopathy 4B, autosomal recessive Pathogenic:1

Sep 01, 2008

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

not provided Other:1

-

TPM3 homepage - Leiden Muscular Dystrophy pages

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		3.7
Mutation Taster		=7/193	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.28		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.28		Position offset: 1

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

Other links and lift over

dbSNP: rs199474719; hg19: chr1-154140415;