rs3729710

Variant summary

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

The NM_000363.5(TNNI3):​c.198G>T​(p.Glu66Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,458,760 control chromosomes in the GnomAD database, with no homozygous occurrence. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E66G) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

TNNI3
NM_000363.5 missense

Scores

1
6
13

Clinical Significance

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

Conservation

PhyloP100: -0.0960
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 156 pathogenic changes around while only 18 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.198G>T p.Glu66Asp missense_variant Exon 5 of 8 ENST00000344887.10 NP_000354.4 P19429Q6FGX2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TNNI3ENST00000344887.10 linkc.198G>T p.Glu66Asp missense_variant Exon 5 of 8 1 NM_000363.5 ENSP00000341838.5 P19429
ENSG00000267110ENST00000587871.1 linkn.*300G>T non_coding_transcript_exon_variant Exon 8 of 9 5 ENSP00000473050.1 M0R381
ENSG00000267110ENST00000587871.1 linkn.*300G>T 3_prime_UTR_variant Exon 8 of 9 5 ENSP00000473050.1 M0R381

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1458760
Hom.:
0
Cov.:
33
AF XY:
0.00000138
AC XY:
1
AN XY:
725636
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000504
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: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hypertrophic cardiomyopathy Uncertain:1
Sep 02, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces glutamic acid, which is acidic and polar, with aspartic acid, which is acidic and polar, at codon 66 of the TNNI3 protein (p.Glu66Asp). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with TNNI3-related conditions. An algorithm developed to predict the effect of missense changes on protein structure and function outputs the following: PolyPhen-2: "Benign". The aspartic acid amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

Cardiovascular phenotype Uncertain:1
Nov 27, 2024
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.E66D variant (also known as c.198G>T), located in coding exon 5 of the TNNI3 gene, results from a G to T substitution at nucleotide position 198. The glutamic acid at codon 66 is replaced by aspartic acid, an amino acid with highly similar properties. This variant has been reported in a hypertrophic cardiomyopathy (HCM) cohorts (Mouton JM et al. Cardiovasc J Afr, 2015;26:63-9; Alfares AA et al. Genet Med, 2015 Nov;17:880-8). This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.094
CardioboostCm
Benign
0.0039
BayesDel_addAF
Benign
-0.015
T
BayesDel_noAF
Benign
-0.26
CADD
Benign
18
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.81
D;D
Eigen
Benign
-0.49
Eigen_PC
Benign
-0.50
FATHMM_MKL
Benign
0.12
N
LIST_S2
Benign
0.63
T;T
M_CAP
Uncertain
0.14
D
MetaRNN
Uncertain
0.51
D;D
MetaSVM
Uncertain
0.25
D
MutationAssessor
Benign
1.8
L;.
PrimateAI
Uncertain
0.70
T
PROVEAN
Benign
-1.6
N;.
REVEL
Uncertain
0.35
Sift
Benign
0.17
T;.
Sift4G
Benign
0.20
T;T
Polyphen
0.0
B;.
Vest4
0.13
MutPred
0.43
Loss of MoRF binding (P = 0.3383);.;
MVP
0.90
MPC
0.60
ClinPred
0.62
D
GERP RS
-0.88
Varity_R
0.39

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs3729710; hg19: chr19-55667653; API