rs369237346

Variant names:

• chr2-178541404-C-T
• rs369237346
• NM_001267550.2:c.97673G>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.97673G>A​(p.Arg32558Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000122 in 1,612,514 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R32558W) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00013 (0 hom.)
• Consequence: TTN NM_001267550.2 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5 B:1
• Conservation: PhyloP100: 7.90
• Publications: 3 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]

ENSG00000270956 (HGNC:):

ACMG classification

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

• BP4: Computational evidence support a benign effect (MetaRNN=0.22692204).

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.97673G>A	p.Arg32558Gln	missense	Exon 350 of 363	NP_001254479.2	Q8WZ42-12
	TTN	NM_001256850.1		c.92750G>A	p.Arg30917Gln	missense	Exon 300 of 313	NP_001243779.1	Q8WZ42-1
	TTN	NM_133378.4		c.89969G>A	p.Arg29990Gln	missense	Exon 299 of 312	NP_596869.4	Q8WZ42-11

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTN	ENST00000589042.5	TSL:5 MANE Select	c.97673G>A	p.Arg32558Gln	missense	Exon 350 of 363	ENSP00000467141.1	Q8WZ42-12
	TTN	ENST00000446966.2	TSL:1	c.97517G>A	p.Arg32506Gln	missense	Exon 348 of 361	ENSP00000408004.2	A0A1B0GXE3
	TTN	ENST00000436599.2	TSL:1	c.97397G>A	p.Arg32466Gln	missense	Exon 348 of 361	ENSP00000405517.2	A0A0C4DG59

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152108 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.000117 AC: 29 AN: 247246 AF XY: 0.000149

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000116

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.000125

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.000134 AC: 195 AN: 1460406 Hom.: 0 Cov.: 32 AF XY: 0.000127 AC XY: 92 AN XY: 726376

African (AFR) AF: 0.0000299 AC: 1 AN: 33448

American (AMR) AF: 0.0000896 AC: 4 AN: 44658

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26088

East Asian (EAS) AF: 0.0000253 AC: 1 AN: 39592

South Asian (SAS) AF: 0.000419 AC: 36 AN: 85938

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53316

Middle Eastern (MID) AF: 0.000174 AC: 1 AN: 5760

European-Non Finnish (NFE) AF: 0.000133 AC: 148 AN: 1111300

Other (OTH) AF: 0.0000663 AC: 4 AN: 60306

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152108 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74290

African (AFR) AF: 0.00 AC: 0 AN: 41420

American (AMR) AF: 0.00 AC: 0 AN: 15260

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5194

South Asian (SAS) AF: 0.000207 AC: 1 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10606

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68006

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.0000901 Hom.: 0

Bravo AF: 0.0000642

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000120 AC: 1

ExAC AF: 0.0000827 AC: 10

Asia WGS AF: 0.000577 AC: 2 AN: 3478

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	3	1	not provided (4)
-	1	-	Cardiomyopathy (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
BayesDel_addAF	Benign	-0.23	T
BayesDel_noAF	Benign	-0.25
CADD	Uncertain	24
DANN	Uncertain	0.99
Eigen	Pathogenic	0.74
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.96	D
M_CAP	Benign	0.042	D
MetaRNN	Benign	0.23	T
MetaSVM	Benign	-0.55	T
MutationAssessor	Benign	1.8	L
PhyloP100		7.9
PrimateAI	Uncertain	0.71	T
PROVEAN	Uncertain	-2.8	D
REVEL	Uncertain	0.36
Sift	Benign	0.10	T
Polyphen		1.0	D
Vest4		0.47
MVP		0.33
MPC		0.50
ClinPred		0.26	T
GERP RS		5.7
Mutation Taster		=95/5	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs369237346; hg19: chr2-179406131; COSMIC: COSV104642929; COSMIC: COSV104642929;