rs757227738

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_003283.6(TNNT1):c.535C>T(p.Arg179Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000587 in 1,584,526 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R179Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 30)

Exomes 𝑓: 0.000063 ( 0 hom. )

Consequence

TNNT1
NM_003283.6 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 1.23

Variant links:

Genes affected

TNNT1 (HGNC:11948): (troponin T1, slow skeletal type) This gene encodes a protein that is a subunit of troponin, which is a regulatory complex located on the thin filament of the sarcomere. This complex regulates striated muscle contraction in response to fluctuations in intracellular calcium concentration. This complex is composed of three subunits: troponin C, which binds calcium, troponin T, which binds tropomyosin, and troponin I, which is an inhibitory subunit. This protein is the slow skeletal troponin T subunit. Mutations in this gene cause nemaline myopathy type 5, also known as Amish nemaline myopathy, a neuromuscular disorder characterized by muscle weakness and rod-shaped, or nemaline, inclusions in skeletal muscle fibers which affects infants, resulting in death due to respiratory insufficiency, usually in the second year. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

TNNT1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.906

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TNNT1	NM_003283.6 linkuse as main transcript	c.535C>T	p.Arg179Trp	missense_variant	11/14	ENST00000588981.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TNNT1	ENST00000588981.6 linkuse as main transcript	c.535C>T	p.Arg179Trp	missense_variant	11/14	1	NM_003283.6		P13805-1

Frequencies

GnomAD3 genomes

AF:

0.0000134

AC:

AN:

148876

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000248

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000148

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000239

AC:

AN:

251066

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135774

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000352

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.0000634

AC:

AN:

1435650

Hom.:

Cov.:

AF XY:

0.0000588

AC XY:

AN XY:

713888

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000266

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000795

Gnomad4 OTH exome

AF:

0.0000342

GnomAD4 genome

AF:

0.0000134

AC:

AN:

148876

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

72480

show subpopulations

Gnomad4 AFR

AF:

0.0000248

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000148

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000843

Hom.:

Bravo

AF:

0.0000227

ExAC

AF:

0.0000247

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Nemaline myopathy 5

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 12, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Mar 18, 2022	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: "Benign"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 465996). This variant has not been reported in the literature in individuals affected with TNNT1-related conditions. This variant is present in population databases (rs757227738, gnomAD 0.006%). This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 179 of the TNNT1 protein (p.Arg179Trp). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.87

BayesDel_addAF

Uncertain

0.15

BayesDel_noAF

Pathogenic

0.15

Cadd

Pathogenic

Dann

Pathogenic

1.0

Eigen

Uncertain

0.56

Eigen_PC

Uncertain

0.41

FATHMM_MKL

Uncertain

0.82

M_CAP

Pathogenic

0.63

MetaRNN

Pathogenic

0.91

D;D;D;D;D;D;D;D;D

MetaSVM

Pathogenic

0.98

MutationTaster

Benign

1.0

D;D;D;D;D;D;D;D

PrimateAI

Pathogenic

0.83

Sift4G

Pathogenic

0.0010

D;D;D;D;D;D;D;D;.

Polyphen

1.0

D;D;D;.;D;.;.;.;.

Vest4

0.73

MutPred

0.71

.;.;Loss of disorder (P = 6e-04);.;Loss of disorder (P = 6e-04);.;.;.;Loss of disorder (P = 6e-04);

MVP

1.0

MPC

0.74

ClinPred

0.98

GERP RS

3.0

RBP_binding_hub_radar

0.92

RBP_regulation_power_radar

2.0

Varity_R

0.79

gMVP

0.58

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over