11-1926716-C-T

Variant names:

• chr11-1926716-C-T
• rs188811451
• NM_006757.4:c.82+7C>T

Variant summary

Our verdict is Benign. Variant got -16 ACMG points: 0P and 16B. BP4_Strong BP6_Very_Strong BS2

The NM_006757.4(TNNT3):​c.82+7C>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000348 in 1,613,170 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0019 (2 hom., cov: 33)
  • Exomes 𝑓: 0.00019 (0 hom.)
• Consequence: TNNT3 NM_006757.4 splice_region, intron
• Scores: Splicing: ADA: 0.00001508
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:2
• Conservation: PhyloP100: -3.09

Genes affected

TNNT3 (HGNC:11950): (troponin T3, fast skeletal type) The binding of Ca(2+) to the trimeric troponin complex initiates the process of muscle contraction. Increased Ca(2+) concentrations produce a conformational change in the troponin complex that is transmitted to tropomyosin dimers situated along actin filaments. The altered conformation permits increased interaction between a myosin head and an actin filament which, ultimately, produces a muscle contraction. The troponin complex has protein subunits C, I, and T. Subunit C binds Ca(2+) and subunit I binds to actin and inhibits actin-myosin interaction. Subunit T binds the troponin complex to the tropomyosin complex and is also required for Ca(2+)-mediated activation of actomyosin ATPase activity. There are 3 different troponin T genes that encode tissue-specific isoforms of subunit T for fast skeletal-, slow skeletal-, and cardiac-muscle. This gene encodes fast skeletal troponin T protein; also known as troponin T type 3. Alternative splicing results in multiple transcript variants encoding additional distinct troponin T type 3 isoforms. A developmentally regulated switch between fetal/neonatal and adult troponin T type 3 isoforms occurs. Additional splice variants have been described but their biological validity has not been established. Mutations in this gene may cause distal arthrogryposis multiplex congenita type 2B (DA2B). [provided by RefSeq, Oct 2009]

ACMG classification

Verdict is Benign. Variant got -16 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.95).
• BP6: Variant 11-1926716-C-T is Benign according to our data. Variant chr11-1926716-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 260031.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BS2: High AC in GnomAd4 at 285 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TNNT3	NM_006757.4	c.82+7C>T		splice_region_variant, intron_variant	Intron 6 of 15	ENST00000278317.11	NP_006748.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TNNT3	ENST00000278317.11	c.82+7C>T		splice_region_variant, intron_variant	Intron 6 of 15	5	NM_006757.4	ENSP00000278317.6

Frequencies

GnomAD3 genomes AF: 0.00181 AC: 276 AN: 152152 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00606

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00105

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000294

Gnomad OTH AF: 0.00287

GnomAD3 exomes AF: 0.000503 AC: 126 AN: 250590 Hom.: 0 AF XY: 0.000354 AC XY: 48 AN XY: 135628

Gnomad AFR exome AF: 0.00679

Gnomad AMR exome AF: 0.000173

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: 0.0000353

Gnomad OTH exome AF: 0.000817

GnomAD4 exome AF: 0.000189 AC: 276 AN: 1460900 Hom.: 0 Cov.: 34 AF XY: 0.000153 AC XY: 111 AN XY: 726786

Gnomad4 AFR exome AF: 0.00621

Gnomad4 AMR exome AF: 0.000291

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000108

Gnomad4 OTH exome AF: 0.000662

GnomAD4 genome AF: 0.00187 AC: 285 AN: 152270 Hom.: 2 Cov.: 33 AF XY: 0.00189 AC XY: 141 AN XY: 74462

Gnomad4 AFR AF: 0.00626

Gnomad4 AMR AF: 0.00105

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000208

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00284

Alfa AF: 0.00117 Hom.: 0

Bravo AF: 0.00231

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:1

-

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Benign:1

Jan 06, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.95
CADD	Benign	0.47
DANN	Benign	0.59

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000015
dbscSNV1_RF	Benign	0.0
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

Other links and lift over

dbSNP: rs188811451; hg19: chr11-1947946;