NM_003283.6:c.814C>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_003283.6(TNNT1):​c.814C>T​(p.Arg272Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000249 in 1,603,628 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. R272H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

TNNT1
NM_003283.6 missense

Scores

8
8
3

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.91

Publications

1 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 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TNNT1NM_003283.6 linkc.814C>T p.Arg272Cys 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.814C>T p.Arg272Cys missense_variant Exon 14 of 14 1 NM_003283.6 ENSP00000467176.1 P13805-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152128
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000434
AC:
1
AN:
230614
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.0000700
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000207
AC:
3
AN:
1451500
Hom.:
0
Cov.:
31
AF XY:
0.00000139
AC XY:
1
AN XY:
720890
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33404
American (AMR)
AF:
0.00
AC:
0
AN:
43096
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25766
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39414
South Asian (SAS)
AF:
0.0000119
AC:
1
AN:
83820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51908
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5756
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1108302
Other (OTH)
AF:
0.00
AC:
0
AN:
60034
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.442
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.00000657
AC:
1
AN:
152128
Hom.:
0
Cov.:
31
AF XY:
0.0000135
AC XY:
1
AN XY:
74308
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41432
American (AMR)
AF:
0.00
AC:
0
AN:
15266
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10584
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.0000282
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.0000165
AC:
2
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
May 18, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.814C>T (p.R272C) alteration is located in exon 14 (coding exon 13) of the TNNT1 gene. This alteration results from a C to T substitution at nucleotide position 814, causing the arginine (R) at amino acid position 272 to be replaced by a cysteine (C). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.81
BayesDel_addAF
Pathogenic
0.21
D
BayesDel_noAF
Uncertain
0.060
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.35
.;.;.;T;D;.;.;.
Eigen
Uncertain
0.36
Eigen_PC
Uncertain
0.33
FATHMM_MKL
Benign
0.49
N
LIST_S2
Pathogenic
0.98
.;D;D;D;D;D;.;.
M_CAP
Pathogenic
0.62
D
MetaRNN
Uncertain
0.45
T;T;T;T;T;T;T;T
MetaSVM
Uncertain
0.75
D
MutationAssessor
Uncertain
2.1
.;.;.;.;M;.;.;.
PhyloP100
1.9
PrimateAI
Pathogenic
0.80
T
PROVEAN
Uncertain
-2.7
.;D;.;.;.;.;.;.
REVEL
Pathogenic
0.74
Sift
Pathogenic
0.0
.;D;.;.;.;.;.;.
Sift4G
Uncertain
0.0040
D;D;D;D;D;D;D;D
Polyphen
1.0
D;D;D;.;D;.;.;.
Vest4
0.42
MutPred
0.43
.;.;.;.;Gain of helix (P = 6e-04);.;.;.;
MVP
0.98
MPC
1.8
ClinPred
0.97
D
GERP RS
2.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.46
gMVP
0.26
Mutation Taster
=76/24
polymorphism

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: rs773089986; hg19: chr19-55644306; API