rs1057518784

chr19-55156289-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1 PM2 BP4_Moderate

The NM_000363.5(TNNI3):c.194C>T(p.Ala65Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,458,648 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A65A) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: TNNI3 NM_000363.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: -0.0360

Genes affected

TNNI3 (HGNC:11947): (troponin I3, cardiac type) Troponin I (TnI), along with troponin T (TnT) and troponin C (TnC), is one of 3 subunits that form the troponin complex of the thin filaments of striated muscle. TnI is the inhibitory subunit; blocking actin-myosin interactions and thereby mediating striated muscle relaxation. The TnI subfamily contains three genes: TnI-skeletal-fast-twitch, TnI-skeletal-slow-twitch, and TnI-cardiac. This gene encodes the TnI-cardiac protein and is exclusively expressed in cardiac muscle tissues. Mutations in this gene cause familial hypertrophic cardiomyopathy type 7 (CMH7) and familial restrictive cardiomyopathy (RCM). Troponin I is useful in making a diagnosis of heart failure, and of ischemic heart disease. An elevated level of troponin is also now used as indicator of acute myocardial injury in patients hospitalized with moderate/severe Coronavirus Disease 2019 (COVID-19). Such elevation has also been associated with higher risk of mortality in cardiovascular disease patients hospitalized due to COVID-19. [provided by RefSeq, Aug 2020]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM1: In a chain Troponin I, cardiac muscle (size 208) in uniprot entity TNNI3_HUMAN there are 152 pathogenic changes around while only 19 benign (89%) in NM_000363.5
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.20840925).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TNNI3	NM_000363.5	c.194C>T	p.Ala65Val	missense_variant	5/8	ENST00000344887.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TNNI3	ENST00000344887.10	c.194C>T	p.Ala65Val	missense_variant	5/8	1	NM_000363.5	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000423 AC: 1 AN: 236282 Hom.: 0 AF XY: 0.00000769 AC XY: 1 AN XY: 130102

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000334

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1458648 Hom.: 0 Cov.: 33 AF XY: 0.00000413 AC XY: 3 AN XY: 725566

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000233

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000312 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Cardiomyopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Nov 01, 2023

This missense variant replaces alanine with valine at codon 65 of the TNNI3 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with TNNI3-related disorders in the literature. This variant has been identified in 1/236282 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Primary dilated cardiomyopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Centre for Mendelian Genomics, University Medical Centre Ljubljana

Oct 27, 2015

- -

Hypertrophic cardiomyopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Dec 13, 2023

This missense variant replaces alanine with valine at codon 65 of the TNNI3 protein. Computational prediction tool suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <=0.5, PMID: 27666373). Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been performed for this variant. This variant has not been reported in individuals affected with cardiovascular disorders in the literature. This variant has been identified in 1/236282 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 30, 2021

The p.A65V variant (also known as c.194C>T), located in coding exon 5 of the TNNI3 gene, results from a C to T substitution at nucleotide position 194. The alanine at codon 65 is replaced by valine, an amino acid with similar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.091
CardioboostCm	Benign	0.00080
BayesDel_addAF	Uncertain	0.13	D
BayesDel_noAF	Uncertain	-0.050
Cadd	Benign	22
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.72	D;D
Eigen	Benign	-0.60
Eigen_PC	Benign	-0.53
FATHMM_MKL	Benign	0.068	N
LIST_S2	Benign	0.15	T;T
M_CAP	Uncertain	0.11	D
MetaRNN	Benign	0.21	T;T
MetaSVM	Benign	-0.38	T
MutationAssessor	Benign	1.1	L;.
MutationTaster	Benign	0.99	N;N
PrimateAI	Uncertain	0.59	T
PROVEAN	Benign	-1.1	N;.
REVEL	Uncertain	0.47
Sift	Benign	0.23	T;.
Sift4G	Benign	0.28	T;T
Polyphen		0.11	B;.
Vest4		0.12
MutPred		0.59		Gain of MoRF binding (P = 0.3016);.;
MVP		0.85
MPC		0.66
ClinPred		0.11	T
GERP RS		2.1
Varity_R		0.15

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: rs1057518784; hg19: chr19-55667657;