NM_001267550.2:c.7534G>A

Variant names:

• chr2-178773522-C-T
• rs116049561
• NM_001267550.2:c.7534G>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_001267550.2(TTN):​c.7534G>A​(p.Glu2512Lys) variant causes a missense change. The variant allele was found at a frequency of 0.000044 in 1,614,006 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000047 (0 hom.)
• Consequence: TTN NM_001267550.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 5.00
• Publications: 4 publications found

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]

TTN-AS1 (HGNC:44124): (TTN antisense RNA 1) This gene encodes a non-coding RNA transcribed from the opposite strand to the titin gene. [provided by RefSeq, Aug 2016]

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.23535019).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001267550.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTN	NM_001267550.2	MANE Select	c.7534G>A	p.Glu2512Lys	missense	Exon 32 of 363	NP_001254479.2
	TTN	NM_001256850.1		c.7534G>A	p.Glu2512Lys	missense	Exon 32 of 313	NP_001243779.1
	TTN	NM_133378.4		c.7534G>A	p.Glu2512Lys	missense	Exon 32 of 312	NP_596869.4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTN	ENST00000589042.5	TSL:5 MANE Select	c.7534G>A	p.Glu2512Lys	missense	Exon 32 of 363	ENSP00000467141.1
	TTN	ENST00000446966.2	TSL:1	c.7534G>A	p.Glu2512Lys	missense	Exon 32 of 361	ENSP00000408004.2
	TTN	ENST00000436599.2	TSL:1	c.7258G>A	p.Glu2420Lys	missense	Exon 30 of 361	ENSP00000405517.2

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152122 Hom.: 0 Cov.: 32

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000199 AC: 5 AN: 250976 AF XY: 0.0000221

Gnomad AFR exome AF: 0.0000615

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: 0.0000353

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000465 AC: 68 AN: 1461766 Hom.: 0 Cov.: 33 AF XY: 0.0000440 AC XY: 32 AN XY: 727184

African (AFR) AF: 0.0000299 AC: 1 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44706

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39674

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53406

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.0000576 AC: 64 AN: 1111956

Other (OTH) AF: 0.0000497 AC: 3 AN: 60392

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152240 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74418

African (AFR) AF: 0.0000241 AC: 1 AN: 41532

American (AMR) AF: 0.00 AC: 0 AN: 15286

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5182

South Asian (SAS) AF: 0.00 AC: 0 AN: 4824

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10612

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.0000294 AC: 2 AN: 68020

Other (OTH) AF: 0.00 AC: 0 AN: 2108

Alfa AF: 0.000171 Hom.: 0

Bravo AF: 0.0000227

ExAC AF: 0.0000247 AC: 3

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	1	-	Autosomal recessive limb-girdle muscular dystrophy type 2J;C1838244:Tibial muscular dystrophy;C1858763:Dilated cardiomyopathy 1G;C1861065:Hypertrophic cardiomyopathy 9;C1863599:Myopathy, myofibrillar, 9, with early respiratory failure;C2673677:Early-onset myopathy with fatal cardiomyopathy (1)
-	1	-	Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G (1)
-	1	-	Cardiomyopathy (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.17
BayesDel_addAF	Uncertain	0.070	D
BayesDel_noAF	Uncertain	-0.030
CADD	Uncertain	24
DANN	Uncertain	0.98
Eigen	Uncertain	0.59
Eigen_PC	Uncertain	0.57
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.97	D
M_CAP	Benign	0.042	D
MetaRNN	Benign	0.24	T
MetaSVM	Uncertain	-0.036	T
PhyloP100		5.0
PrimateAI	Uncertain	0.60	T
PROVEAN	Uncertain	-2.5	N
REVEL	Uncertain	0.42
Sift	Benign	0.51	T
Sift4G	Uncertain	0.010	D
Polyphen		0.96	D
Vest4		0.39
MVP		0.51
MPC		0.24
ClinPred		0.28	T
GERP RS		5.8
Mutation Taster		=86/14	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.16		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs116049561; hg19: chr2-179638249; COSMIC: COSV60177110; COSMIC: COSV60177110;