rs757537780

Variant names:

• chr2-178581700-C-G
• rs757537780
• NM_001267550.2:c.66568G>C

Your query was ambiguous. Multiple possible variants found:

• chr2-178581700-C-G
• chr2-178581700-C-T

Variant summary

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

The NM_001267550.2(TTN):​c.66568G>C​(p.Gly22190Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000141 in 1,611,812 control chromosomes in the GnomAD database, including 1 homozygotes. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.000033 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00015 (1 hom.)
• Consequence: TTN NM_001267550.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:7
• Conservation: PhyloP100: 7.86
• 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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTN	NM_001267550.2	MANE Select	c.66568G>C	p.Gly22190Arg	missense	Exon 316 of 363	NP_001254479.2
	TTN	NM_001256850.1		c.61645G>C	p.Gly20549Arg	missense	Exon 266 of 313	NP_001243779.1
	TTN	NM_133378.4		c.58864G>C	p.Gly19622Arg	missense	Exon 265 of 312	NP_596869.4

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTN	ENST00000589042.5	TSL:5 MANE Select	c.66568G>C	p.Gly22190Arg	missense	Exon 316 of 363	ENSP00000467141.1
	TTN	ENST00000446966.2	TSL:1	c.66412G>C	p.Gly22138Arg	missense	Exon 314 of 361	ENSP00000408004.2
	TTN	ENST00000436599.2	TSL:1	c.66292G>C	p.Gly22098Arg	missense	Exon 314 of 361	ENSP00000405517.2

Frequencies

GnomAD3 genomes AF: 0.0000329 AC: 5 AN: 152036 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000724

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: 0.0000122 AC: 3 AN: 245838 AF XY: 0.00000750

Gnomad AFR exome AF: 0.0000655

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: 0.0000180

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.000152 AC: 222 AN: 1459776 Hom.: 1 Cov.: 32 AF XY: 0.000157 AC XY: 114 AN XY: 726122

African (AFR) AF: 0.0000898 AC: 3 AN: 33418

American (AMR) AF: 0.00 AC: 0 AN: 44570

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26084

East Asian (EAS) AF: 0.00 AC: 0 AN: 39386

South Asian (SAS) AF: 0.00 AC: 0 AN: 86080

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53240

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5754

European-Non Finnish (NFE) AF: 0.000195 AC: 217 AN: 1110968

Other (OTH) AF: 0.0000332 AC: 2 AN: 60276

GnomAD4 genome AF: 0.0000329 AC: 5 AN: 152036 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74220

African (AFR) AF: 0.0000724 AC: 3 AN: 41420

American (AMR) AF: 0.00 AC: 0 AN: 15250

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5152

South Asian (SAS) AF: 0.00 AC: 0 AN: 4822

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10618

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

European-Non Finnish (NFE) AF: 0.0000294 AC: 2 AN: 67984

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

Alfa AF: 0.0000282 Hom.: 0

Bravo AF: 0.0000151

ExAC AF: 0.00000829 AC: 1

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	2	-	not provided (2)
-	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	-	Cardiovascular phenotype (1)
-	1	-	not specified (1)
-	1	-	Sudden cardiac arrest (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Uncertain	0.040	T
BayesDel_noAF	Uncertain	0.0
CADD	Benign	22
DANN	Benign	0.97
Eigen	Pathogenic	0.92
Eigen_PC	Pathogenic	0.88
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D
M_CAP	Benign	0.022	T
MetaRNN	Uncertain	0.58	D
MetaSVM	Uncertain	-0.089	T
MutationAssessor	Uncertain	2.6	M
PhyloP100		7.9
PrimateAI	Pathogenic	0.85	D
PROVEAN	Pathogenic	-6.2	D
REVEL	Uncertain	0.57
Sift	Uncertain	0.0010	D
Polyphen		1.0	D
Vest4		0.63
MutPred		0.71		Gain of MoRF binding (P = 0.057)
MVP		0.65
MPC		0.51
ClinPred		0.77	D
GERP RS		5.4
Mutation Taster		=75/25	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: rs757537780; hg19: chr2-179446427;