15-63061781-C-G

Position:

• chr15-63061781-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP3_Moderate

The NM_001018005.2(TPM1):​c.632C>G​(p.Ala211Gly) variant causes a missense change involving the alteration of a conserved nucleotide. 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 Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: TPM1 NM_001018005.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.91

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 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a chain Tropomyosin alpha-1 chain (size 283) in uniprot entity TPM1_HUMAN there are 61 pathogenic changes around while only 1 benign (98%) in NM_001018005.2
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), TPM1. . Gene score misZ 2.8677 (greater than the threshold 3.09). Trascript score misZ 3.9402 (greater than threshold 3.09). GenCC has associacion of gene with dilated cardiomyopathy, left ventricular noncompaction, hypertrophic cardiomyopathy, hypertrophic cardiomyopathy 3, arrhythmogenic right ventricular cardiomyopathy, familial isolated dilated cardiomyopathy, dilated cardiomyopathy 1Y.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.852

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TPM1	NM_001018005.2	c.632C>G	p.Ala211Gly	missense_variant	6/10	ENST00000403994.9	NP_001018005.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TPM1	ENST00000403994.9	c.632C>G	p.Ala211Gly	missense_variant	6/10	1	NM_001018005.2	ENSP00000385107.4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Jul 22, 2015

Variant classified as Uncertain Significance - Favor Pathogenic. The p.Ala211Gly variant in TPM1 has been previously identified by our laboratory in 1 Caucasian adult with DCM (Lakdawala 2012). Limited family studies are consistent with a disease causing role but insufficient to establish this with certainty (LMM unpu blished data). This variant was absent from large population studies (dbSNP rs39 7516487). Alanine (Ala) at position 211 is highly conserved in evolution and the change to glycine (Gly) was predicted to be pathogenic using a computational to ol clinically validated by our laboratory. This tool's pathogenic prediction is estimated to be correct 94% of the time (Jordan 2011). However, this information is not predictive enough to determine pathogenicity. In summary, while there is some suspicion for a pathogenic role, the clinical significance of the p.Ala211 Gly variant is uncertain. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.26
CardioboostCm	Uncertain	0.89
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.51
CADD	Pathogenic	34
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.92	D;D;.;.;.;.;.;.;D
Eigen	Uncertain	0.58
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Benign	0.79	T;T;T;T;T;T;T;T;T
M_CAP	Pathogenic	0.41	D
MetaRNN	Pathogenic	0.85	D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.7	H;.;H;H;H;.;.;.;.
PROVEAN	Benign	-1.9	N;N;N;N;.;.;N;.;N
REVEL	Pathogenic	0.68
Sift	Benign	0.051	T;D;D;D;.;.;D;.;D
Sift4G	Benign	0.10	T;D;T;T;.;.;T;.;T
Polyphen		0.070	B;B;.;.;B;.;.;.;.
Vest4		0.80
MutPred		0.62		.;Gain of methylation at K255 (P = 0.1893);.;.;.;.;.;.;.;
MVP		0.98
ClinPred		0.98	D
GERP RS		6.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.52

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.71		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.71		Position offset: -1

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

Publications

LitVar

Other links and lift over

dbSNP: rs397516487; hg19: chr15-63353980;