15-63064075-G-T

Variant names:

• chr15-63064075-G-T
• rs758506771
• NM_001018005.2:c.784G>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 4P and 2B. PM1 PM2 BP4_Moderate

The NM_001018005.2(TPM1):​c.784G>T​(p.Ala262Ser) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,690 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A262T) has been classified as Uncertain significance. The gene TPM1 is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: TPM1 NM_001018005.2 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 4.50
• Publications: 3 publications found

Genes affected

TPM1 (HGNC:12010): (tropomyosin 1) This gene is a member of the tropomyosin family of highly conserved, widely distributed actin-binding proteins involved in the contractile system of striated and smooth muscles and the cytoskeleton of non-muscle cells. Tropomyosin is composed of two alpha-helical chains arranged as a coiled-coil. It is polymerized end to end along the two grooves of actin filaments and provides stability to the filaments. The encoded protein is one type of alpha helical chain that forms the predominant tropomyosin of striated muscle, where it also functions in association with the troponin complex to regulate the calcium-dependent interaction of actin and myosin during muscle contraction. In smooth muscle and non-muscle cells, alternatively spliced transcript variants encoding a range of isoforms have been described. Mutations in this gene are associated with type 3 familial hypertrophic cardiomyopathy and dilated cardiomyopathy 1Y. [provided by RefSeq, Jun 2022]

TPM1 Gene-Disease associations (from GenCC):

• hypertrophic cardiomyopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• hypertrophic cardiomyopathy 3

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• dilated cardiomyopathy 1Y

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• dilated cardiomyopathy

  Inheritance: AD Classification: MODERATE Submitted by: ClinGen
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• left ventricular noncompaction

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• arrhythmogenic right ventricular cardiomyopathy

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Specifications for TPM1 are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 16 uncertain in NM_001018005.2
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.22161904).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001018005.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TPM1	NM_001018005.2	MANE Select	c.784G>T	p.Ala262Ser	missense	Exon 9 of 10	NP_001018005.1	D9YZV4
	TPM1	NM_001407322.1		c.910G>T	p.Ala304Ser	missense	Exon 10 of 11	NP_001394251.1
	TPM1	NM_001407323.1		c.910G>T	p.Ala304Ser	missense	Exon 10 of 11	NP_001394252.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TPM1	ENST00000403994.9	TSL:1 MANE Select	c.784G>T	p.Ala262Ser	missense	Exon 9 of 10	ENSP00000385107.4	P09493-1
	TPM1	ENST00000288398.10	TSL:1	c.784G>T	p.Ala262Ser	missense	Exon 9 of 10	ENSP00000288398.6	P09493-10
	TPM1	ENST00000560970.6	TSL:1	c.784G>T	p.Ala262Ser	missense	Exon 9 of 10	ENSP00000453062.2	A0A0S2Z4G6

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461690 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727132

African (AFR) AF: 0.0000299 AC: 1 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44716

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86222

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53294

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111980

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.059
CardioboostCm	Benign	0.0073
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	-0.070
CADD	Uncertain	24
DANN	Benign	0.93
DEOGEN2	Uncertain	0.69	D
Eigen	Benign	-0.18
Eigen_PC	Benign	0.041
FATHMM_MKL	Uncertain	0.89	D
LIST_S2	Uncertain	0.89	D
M_CAP	Benign	0.064	D
MetaRNN	Benign	0.22	T
MetaSVM	Uncertain	0.36	D
MutationAssessor	Benign	0.56	N
PhyloP100		4.5
PROVEAN	Benign	-0.42	N
REVEL	Uncertain	0.47
Sift	Benign	0.57	T
Sift4G	Benign	0.42	T
Polyphen		0.0	B
Vest4		0.26
MutPred		0.54		Gain of disorder (P = 0.0432)
MVP		0.46
ClinPred		0.45	T
GERP RS		5.8
Varity_R		0.22
Mutation Taster		=79/21	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs758506771; hg19: chr15-63356274;