19-55132926-G-A

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 0P and 0B.

The NM_003283.6(TNNT1):​c.826C>T​(p.Arg276Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000231 in 1,603,618 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000024 ( 0 hom. )

Consequence

TNNT1
NM_003283.6 missense

Scores

4
11
4

Clinical Significance

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

Conservation

PhyloP100: 7.58

Publications

0 publications found
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 Gene-Disease associations (from GenCC):
  • nemaline myopathy 5
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae)
  • nemaline myopathy
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen
  • nemaline myopathy 5C, autosomal dominant
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TNNT1NM_003283.6 linkc.826C>T p.Arg276Cys missense_variant Exon 14 of 14 ENST00000588981.6 NP_003274.3 P13805-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TNNT1ENST00000588981.6 linkc.826C>T p.Arg276Cys missense_variant Exon 14 of 14 1 NM_003283.6 ENSP00000467176.1 P13805-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152166
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000192
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000173
AC:
4
AN:
230828
AF XY:
0.0000160
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000115
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000192
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000241
AC:
35
AN:
1451334
Hom.:
0
Cov.:
31
AF XY:
0.0000277
AC XY:
20
AN XY:
720802
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33402
American (AMR)
AF:
0.0000232
AC:
1
AN:
43080
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25754
East Asian (EAS)
AF:
0.000152
AC:
6
AN:
39400
South Asian (SAS)
AF:
0.0000119
AC:
1
AN:
83784
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51936
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5754
European-Non Finnish (NFE)
AF:
0.0000208
AC:
23
AN:
1108194
Other (OTH)
AF:
0.0000666
AC:
4
AN:
60030
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
2
4
7
9
11
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152284
Hom.:
0
Cov.:
31
AF XY:
0.0000269
AC XY:
2
AN XY:
74468
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41562
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68018
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000340
ExAC
AF:
0.0000165
AC:
2

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
Oct 16, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 276 of the TNNT1 protein (p.Arg276Cys). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with TNNT1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1028592). 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. 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. -

Mar 02, 2019
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.92
BayesDel_addAF
Uncertain
0.054
T
BayesDel_noAF
Benign
-0.16
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.38
.;.;.;T;D;.;.;.
Eigen
Pathogenic
0.74
Eigen_PC
Uncertain
0.65
FATHMM_MKL
Uncertain
0.88
D
LIST_S2
Uncertain
0.94
.;D;D;D;D;D;.;.
M_CAP
Uncertain
0.23
D
MetaRNN
Uncertain
0.56
D;D;D;D;D;D;D;D
MetaSVM
Benign
-0.75
T
MutationAssessor
Uncertain
2.8
.;.;.;.;M;.;.;.
PhyloP100
7.6
PrimateAI
Uncertain
0.77
T
PROVEAN
Uncertain
-3.7
.;D;.;.;.;.;.;.
REVEL
Uncertain
0.46
Sift
Uncertain
0.0090
.;D;.;.;.;.;.;.
Sift4G
Pathogenic
0.0
D;D;D;D;D;D;D;D
Polyphen
1.0
D;D;D;.;D;.;.;.
Vest4
0.56
MVP
0.76
MPC
1.8
ClinPred
0.98
D
GERP RS
4.0
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.41
gMVP
0.46
Mutation Taster
=42/58
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs201409131; hg19: chr19-55644294; API