rs751610164

Variant names:

• chr2-178551179-C-T
• rs751610164
• NM_001267550.2:c.91352G>A

Variant summary

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

The NM_001267550.2(TTN):​c.91352G>A​(p.Gly30451Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000031 in 1,613,470 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000034 (0 hom.)
• Consequence: TTN NM_001267550.2 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:10 B:2
• Conservation: PhyloP100: 7.91
• Publications: 1 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: Uncertain_significance. The variant received 0 ACMG points.

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.91352G>A	p.Gly30451Asp	missense	Exon 336 of 363	NP_001254479.2	Q8WZ42-12
	TTN	NM_001256850.1		c.86429G>A	p.Gly28810Asp	missense	Exon 286 of 313	NP_001243779.1	Q8WZ42-1
	TTN	NM_133378.4		c.83648G>A	p.Gly27883Asp	missense	Exon 285 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.91352G>A	p.Gly30451Asp	missense	Exon 336 of 363	ENSP00000467141.1	Q8WZ42-12
	TTN	ENST00000446966.2	TSL:1	c.91196G>A	p.Gly30399Asp	missense	Exon 334 of 361	ENSP00000408004.2	A0A1B0GXE3
	TTN	ENST00000436599.2	TSL:1	c.91076G>A	p.Gly30359Asp	missense	Exon 334 of 361	ENSP00000405517.2	A0A0C4DG59

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152114 Hom.: 0 Cov.: 33

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: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000282 AC: 7 AN: 248586 AF XY: 0.0000222

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: 0.0000267

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000335 AC: 49 AN: 1461356 Hom.: 0 Cov.: 31 AF XY: 0.0000248 AC XY: 18 AN XY: 726962

African (AFR) AF: 0.00 AC: 0 AN: 33452

American (AMR) AF: 0.000134 AC: 6 AN: 44712

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26122

East Asian (EAS) AF: 0.00 AC: 0 AN: 39652

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

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53380

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.0000387 AC: 43 AN: 1111660

Other (OTH) AF: 0.00 AC: 0 AN: 60360

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152114 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74312

African (AFR) AF: 0.00 AC: 0 AN: 41412

American (AMR) AF: 0.00 AC: 0 AN: 15256

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5192

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10608

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

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68028

Other (OTH) AF: 0.00 AC: 0 AN: 2090

Alfa AF: 0.0000774 Hom.: 0

Bravo AF: 0.0000227

ExAC AF: 0.0000248 AC: 3

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	3	-	not provided (3)
-	2	-	not specified (2)
-	1	-	Autosomal recessive limb-girdle muscular dystrophy type 2J (1)
-	1	-	Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G (1)
-	1	-	Cardiovascular phenotype (1)
-	1	-	Dilated cardiomyopathy 1G (1)
-	1	-	Early-onset myopathy with fatal cardiomyopathy (1)
-	-	1	Myopathy, myofibrillar, 9, with early respiratory failure (1)
-	-	1	Tibial muscular dystrophy (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.94
BayesDel_addAF	Benign	-0.060	T
BayesDel_noAF	Benign	-0.10
CADD	Benign	22
DANN	Uncertain	0.98
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.93
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D
M_CAP	Benign	0.044	D
MetaRNN	Uncertain	0.59	D
MetaSVM	Uncertain	0.084	D
MutationAssessor	Pathogenic	3.5	M
PhyloP100		7.9
PrimateAI	Uncertain	0.72	T
PROVEAN	Pathogenic	-5.3	D
REVEL	Uncertain	0.47
Sift	Uncertain	0.0010	D
Polyphen		1.0	D
Vest4		0.73
MVP		0.45
MPC		0.52
ClinPred		0.57	D
GERP RS		5.9
Mutation Taster		=53/47	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
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

Other links and lift over

dbSNP: rs751610164; hg19: chr2-179415906;