rs1555864366

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1PM2

The NM_000363.5(TNNI3):​c.79C>T​(p.Arg27Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

TNNI3
NM_000363.5 missense

Scores

6
10
4

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts P:1U:2

Conservation

PhyloP100: 1.44
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 Uncertain_significance. Variant got 4 ACMG points.

PM1
In a chain Troponin I, cardiac muscle (size 208) in uniprot entity TNNI3_HUMAN there are 86 pathogenic changes around while only 10 benign (90%) in NM_000363.5
PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TNNI3NM_000363.5 linkc.79C>T p.Arg27Cys missense_variant Exon 3 of 8 ENST00000344887.10 NP_000354.4 P19429Q6FGX2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TNNI3ENST00000344887.10 linkc.79C>T p.Arg27Cys missense_variant Exon 3 of 8 1 NM_000363.5 ENSP00000341838.5 P19429
ENSG00000267110ENST00000587871.1 linkn.*181C>T non_coding_transcript_exon_variant Exon 6 of 9 5 ENSP00000473050.1 M0R381
ENSG00000267110ENST00000587871.1 linkn.*181C>T 3_prime_UTR_variant Exon 6 of 9 5 ENSP00000473050.1 M0R381

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
Data not reliable, filtered out with message: AC0
AF:
0.00
AC:
0
AN:
1449060
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
719358
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.:
32

ClinVar

Significance: Uncertain significance
Submissions summary: Pathogenic:1Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Dilated cardiomyopathy 1A Pathogenic:1
-
Cytogenetics- Mohapatra Lab, Banaras Hindu University
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: research

- -

Hypertrophic cardiomyopathy Uncertain:1
May 17, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 835941). This variant has not been reported in the literature in individuals affected with TNNI3-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 27 of the TNNI3 protein (p.Arg27Cys). -

Cardiovascular phenotype Uncertain:1
Nov 15, 2021
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.R27C variant (also known as c.79C>T), located in coding exon 3 of the TNNI3 gene, results from a C to T substitution at nucleotide position 79. The arginine at codon 27 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is well conserved in available vertebrate species. 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
Pathogenic
0.76
CardioboostCm
Uncertain
0.61
BayesDel_addAF
Pathogenic
0.17
D
BayesDel_noAF
Uncertain
0.0
CADD
Pathogenic
28
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.77
D
Eigen
Uncertain
0.28
Eigen_PC
Uncertain
0.26
FATHMM_MKL
Uncertain
0.76
D
LIST_S2
Uncertain
0.93
D
M_CAP
Pathogenic
0.93
D
MetaRNN
Uncertain
0.67
D
MetaSVM
Uncertain
0.66
D
MutationAssessor
Benign
0.97
L
PrimateAI
Pathogenic
0.83
D
PROVEAN
Benign
-1.4
N
REVEL
Pathogenic
0.65
Sift
Benign
0.031
D
Sift4G
Uncertain
0.0030
D
Polyphen
1.0
D
Vest4
0.33
MutPred
0.32
Loss of methylation at R27 (P = 0.0242);
MVP
0.92
MPC
2.0
ClinPred
0.93
D
GERP RS
2.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.17

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

Publications

LitVar

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

Other links and lift over

dbSNP: rs1555864366; hg19: chr19-55668447; COSMIC: COSV105247222; COSMIC: COSV105247222; API