rs767741769

chr2-178782273-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 1P and 0B. PP2

The NM_001267550.2(TTN):c.3319G>A(p.Gly1107Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000136 in 1,613,952 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.000039 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000011 (0 hom.)
• Consequence: TTN NM_001267550.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 7.81

Genes affected

TTN (HGNC:12403): (titin) This gene encodes a large abundant protein of striated muscle. The product of this gene is divided into two regions, a N-terminal I-band and a C-terminal A-band. The I-band, which is the elastic part of the molecule, contains two regions of tandem immunoglobulin domains on either side of a PEVK region that is rich in proline, glutamate, valine and lysine. The A-band, which is thought to act as a protein-ruler, contains a mixture of immunoglobulin and fibronectin repeats, and possesses kinase activity. An N-terminal Z-disc region and a C-terminal M-line region bind to the Z-line and M-line of the sarcomere, respectively, so that a single titin molecule spans half the length of a sarcomere. Titin also contains binding sites for muscle associated proteins so it serves as an adhesion template for the assembly of contractile machinery in muscle cells. It has also been identified as a structural protein for chromosomes. Alternative splicing of this gene results in multiple transcript variants. Considerable variability exists in the I-band, the M-line and the Z-disc regions of titin. Variability in the I-band region contributes to the differences in elasticity of different titin isoforms and, therefore, to the differences in elasticity of different muscle types. Mutations in this gene are associated with familial hypertrophic cardiomyopathy 9, and autoantibodies to titin are produced in patients with the autoimmune disease scleroderma. [provided by RefSeq, Feb 2012]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PP2: Missense variant where missense usually causes diseases, TTN

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TTN	NM_001267550.2	c.3319G>A	p.Gly1107Ser	missense_variant	20/363	ENST00000589042.5
TTN	NM_133379.5	c.3319G>A	p.Gly1107Ser	missense_variant	20/46	ENST00000360870.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TTN	ENST00000589042.5	c.3319G>A	p.Gly1107Ser	missense_variant	20/363	5	NM_001267550.2	P1
TTN	ENST00000360870.10	c.3319G>A	p.Gly1107Ser	missense_variant	20/46	5	NM_133379.5

Frequencies

GnomAD3 genomes AF: 0.0000394 AC: 6 AN: 152112 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000724

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000131

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000199 AC: 5 AN: 251080 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135676

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000353

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.0000109 AC: 16 AN: 1461840 Hom.: 0 Cov.: 32 AF XY: 0.0000124 AC XY: 9 AN XY: 727220

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000108

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.0000394 AC: 6 AN: 152112 Hom.: 0 Cov.: 32 AF XY: 0.0000404 AC XY: 3 AN XY: 74284

Gnomad4 AFR AF: 0.0000724

Gnomad4 AMR AF: 0.000131

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000104 Hom.: 0

Bravo AF: 0.0000604

ExAC AF: 0.0000330 AC: 4

EpiCase AF: 0.0000545

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Feb 28, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Sep 08, 2015	- -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jul 21, 2017

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
BayesDel_addAF	Uncertain	0.058	T
BayesDel_noAF	Uncertain	-0.020
Cadd	Uncertain	25
Dann	Uncertain	0.98
Eigen	Pathogenic	0.92
Eigen_PC	Pathogenic	0.89
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.97	D;D;D;.;D;D;D;D
M_CAP	Benign	0.029	D
MetaRNN	Uncertain	0.48	T;T;T;T;T;T;T;T
MetaSVM	Uncertain	0.52	D
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.63	T
PROVEAN	Uncertain	-4.3	D;D;.;.;D;D;.;D
REVEL	Pathogenic	0.73
Sift	Benign	0.43	T;T;.;.;T;T;.;T
Polyphen		1.0	.;.;.;D;.;.;D;D
Vest4		0.36
MutPred		0.81		Gain of loop (P = 0.1069);.;Gain of loop (P = 0.1069);Gain of loop (P = 0.1069);.;.;Gain of loop (P = 0.1069);Gain of loop (P = 0.1069);
MVP		0.60
MPC		0.46
ClinPred		0.75	D
GERP RS		5.6

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

Other links and lift over

dbSNP: rs767741769; hg19: chr2-179647000;