3-52451451-C-T

Position:

• chr3-52451451-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_003280.3(TNNC1):​c.394G>A​(p.Asp132Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,856 control chromosomes in the GnomAD database, with no homozygous occurrence. 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)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: TNNC1 NM_003280.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.91

Genes affected

TNNC1 (HGNC:11943): (troponin C1, slow skeletal and cardiac type) Troponin is a central regulatory protein of striated muscle contraction, and together with tropomyosin, is located on the actin filament. Troponin consists of 3 subunits: TnI, which is the inhibitor of actomyosin ATPase; TnT, which contains the binding site for tropomyosin; and TnC, the protein encoded by this gene. The binding of calcium to TnC abolishes the inhibitory action of TnI, thus allowing the interaction of actin with myosin, the hydrolysis of ATP, and the generation of tension. Mutations in this gene are associated with cardiomyopathy dilated type 1Z. [provided by RefSeq, Oct 2008]

TNNC1 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a chain Troponin C, slow skeletal and cardiac muscles (size 160) in uniprot entity TNNC1_HUMAN there are 13 pathogenic changes around while only 0 benign (100%) in NM_003280.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.789

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TNNC1	NM_003280.3	c.394G>A	p.Asp132Asn	missense_variant	5/6	ENST00000232975.8	NP_003271.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TNNC1	ENST00000232975.8	c.394G>A	p.Asp132Asn	missense_variant	5/6	1	NM_003280.3	ENSP00000232975.3
TNNC1	ENST00000496590.1	c.262G>A	p.Asp88Asn	missense_variant	4/4	2		ENSP00000420596.1
TNNC1	ENST00000461086.1	n.325G>A		non_coding_transcript_exon_variant	2/2	2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461856 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727226

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000180

Gnomad4 OTH exome AF: 0.00

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 06, 2012

The Asp132Asn variant in TNNC1 has not been reported in the literature nor previ ously identified by our laboratory. In addition, this variant has not been ident ified in large and broad populations by the NHLBI Exome Sequencing Project (http ://evs.gs.washington.edu/EVS). This low frequency is consistent with a disease- causing role but insufficient to establish this with confidence. The affected a mino acid is highly conserved in evolution, suggesting that a change may not be tolerated. Other computational analyses (biochemical amino acid properties, Ali gnGVGD, PolyPhen2, and SIFT) do not provide strong support for or against an imp act to the protein. Additional information is needed to fully assess the clinic al significance of the Asp132Asn variant. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.61
BayesDel_addAF	Benign	-0.018	T
BayesDel_noAF	Benign	-0.26
CADD	Uncertain	25
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.60	D;T
Eigen	Pathogenic	0.76
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D;D
M_CAP	Benign	0.070	D
MetaRNN	Pathogenic	0.79	D;D
MetaSVM	Uncertain	-0.039	T
MutationAssessor	Benign	1.2	L;.
PrimateAI	Pathogenic	0.80	T
PROVEAN	Benign	-1.9	N;N
REVEL	Uncertain	0.45
Sift	Pathogenic	0.0	D;D
Sift4G	Uncertain	0.014	D;.
Polyphen		1.0	D;.
Vest4		0.72
MutPred		0.60		Loss of phosphorylation at T129 (P = 0.1228);.;
MVP		0.83
MPC		1.4
ClinPred		0.99	D
GERP RS		5.6
Varity_R		0.88
gMVP		0.88

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs397516846; hg19: chr3-52485467;