rs727503504

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_000363.5(TNNI3):​c.508C>T​(p.Arg170Trp) variant causes a missense change involving the alteration of a non-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 Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R170Q) has been classified as Pathogenic.

Frequency

Genomes: not found (cov: 31)
Exomes 𝑓: 0.0 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

TNNI3
NM_000363.5 missense

Scores

15
1
4

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 0.109
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PM1
In a helix (size 25) in uniprot entity TNNI3_HUMAN there are 19 pathogenic changes around while only 0 benign (100%) in NM_000363.5
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr19-55154070-C-T is described in Lovd as [Pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.978
PP5
Variant 19-55154071-G-A is Pathogenic according to our data. Variant chr19-55154071-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 179285.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr19-55154071-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TNNI3NM_000363.5 linkc.508C>T p.Arg170Trp missense_variant Exon 7 of 8 ENST00000344887.10 NP_000354.4 P19429Q6FGX2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TNNI3ENST00000344887.10 linkc.508C>T p.Arg170Trp missense_variant Exon 7 of 8 1 NM_000363.5 ENSP00000341838.5 P19429

Frequencies

GnomAD3 genomes
Cov.:
31
GnomAD4 exome
Data not reliable, filtered out with message: AC0
AF:
0.00
AC:
0
AN:
1460534
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
726596
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:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
31

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Restrictive cardiomyopathy Pathogenic:2
Jul 15, 2014
Blueprint Genetics
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

May 12, 2015
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

proposed classification - variant undergoing re-assessment, contact laboratory -

Hypertrophic cardiomyopathy Pathogenic:2
Feb 09, 2017
Center for Human Genetics, University of Leuven
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

ACMG score likely pathogenic -

Jan 06, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 170 of the TNNI3 protein (p.Arg170Trp). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with restrictive cardiomyopathy (internal data). In at least one individual the variant was observed to be de novo. ClinVar contains an entry for this variant (Variation ID: 179285). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. This variant disrupts the p.Arg170 amino acid residue in TNNI3. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 20031618, 25940119, 27532257). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Cardiomyopathy, familial restrictive, 1 Pathogenic:1
Jul 21, 2020
Institute of Human Genetics Munich, Klinikum Rechts Der Isar, TU München
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not provided Pathogenic:1
Feb 06, 2023
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Published functional studies suggest a damaging effect via impaired calcium handling and thin filament dysfunction due to weak actin interaction (Cimiotti et al., 2020); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 28301460, 32182250, 31912959, 33906374, 33429969, 36174041, 35614389, 33583869) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.81
CardioboostCm
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.36
D
BayesDel_noAF
Pathogenic
0.28
CADD
Uncertain
26
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.97
D;D
Eigen
Benign
0.18
Eigen_PC
Benign
-0.044
FATHMM_MKL
Benign
0.20
N
LIST_S2
Pathogenic
1.0
D;D
M_CAP
Pathogenic
0.59
D
MetaRNN
Pathogenic
0.98
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.3
M;.
PrimateAI
Uncertain
0.78
T
PROVEAN
Pathogenic
-7.3
D;.
REVEL
Pathogenic
0.81
Sift
Pathogenic
0.0
D;.
Sift4G
Pathogenic
0.0
D;D
Polyphen
1.0
D;.
Vest4
0.95
MutPred
0.85
Loss of disorder (P = 9e-04);.;
MVP
0.95
MPC
1.7
ClinPred
0.99
D
GERP RS
-1.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.96

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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs727503504; hg19: chr19-55665439; COSMIC: COSV52572862; COSMIC: COSV52572862; API