rs562856820

Variant names:

• chr2-178775989-A-T
• rs562856820
• NM_001267550.2:c.5875T>A

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BS1 BS2

The NM_001267550.2(TTN):​c.5875T>A​(p.Phe1959Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000454 in 1,614,062 control chromosomes in the GnomAD database, including 13 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

• Frequency:
  • Genomes: 𝑓 0.00029 (1 hom., cov: 32)
  • Exomes 𝑓: 0.00047 (12 hom.)
• Consequence: TTN NM_001267550.2 missense
• Clinical Significance: Benign criteria provided, multiple submitters, no conflicts B:12 O:1
• Conservation: PhyloP100: 9.28
• 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: Benign. The variant received -20 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.007751614).
• BP6: Variant 2-178775989-A-T is Benign according to our data. Variant chr2-178775989-A-T is described in ClinVar as Benign. ClinVar VariationId is 203141.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BS1: Variant frequency is greater than expected in population sas. GnomAd4 allele frequency = 0.000289 (44/152212) while in subpopulation SAS AF = 0.00914 (44/4812). AF 95% confidence interval is 0.007. There are 1 homozygotes in GnomAd4. There are 27 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
• BS2: High Homozygotes in GnomAdExome4 at 12 AD,AR gene

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.5875T>A	p.Phe1959Ile	missense	Exon 28 of 363	NP_001254479.2	Q8WZ42-12
	TTN	NM_001256850.1		c.5875T>A	p.Phe1959Ile	missense	Exon 28 of 313	NP_001243779.1	Q8WZ42-1
	TTN	NM_133378.4		c.5875T>A	p.Phe1959Ile	missense	Exon 28 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.5875T>A	p.Phe1959Ile	missense	Exon 28 of 363	ENSP00000467141.1	Q8WZ42-12
	TTN	ENST00000446966.2	TSL:1	c.5875T>A	p.Phe1959Ile	missense	Exon 28 of 361	ENSP00000408004.2	A0A1B0GXE3
	TTN	ENST00000436599.2	TSL:1	c.5599T>A	p.Phe1867Ile	missense	Exon 26 of 361	ENSP00000405517.2	A0A0C4DG59

Frequencies

GnomAD3 genomes AF: 0.000289 AC: 44 AN: 152094 Hom.: 1 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: 0.00914

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00100 AC: 252 AN: 251176 AF XY: 0.00136

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000653

GnomAD4 exome AF: 0.000471 AC: 689 AN: 1461850 Hom.: 12 Cov.: 33 AF XY: 0.000690 AC XY: 502 AN XY: 727230

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

American (AMR) AF: 0.0000447 AC: 2 AN: 44722

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00745 AC: 643 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

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

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111978

Other (OTH) AF: 0.000662 AC: 40 AN: 60394

GnomAD4 genome AF: 0.000289 AC: 44 AN: 152212 Hom.: 1 Cov.: 32 AF XY: 0.000363 AC XY: 27 AN XY: 74410

African (AFR) AF: 0.00 AC: 0 AN: 41544

American (AMR) AF: 0.00 AC: 0 AN: 15280

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5170

South Asian (SAS) AF: 0.00914 AC: 44 AN: 4812

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10600

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68014

Other (OTH) AF: 0.00 AC: 0 AN: 2116

Alfa AF: 0.0000943 Hom.: 0

Bravo AF: 0.0000529

ExAC AF: 0.00110 AC: 134

Asia WGS AF: 0.00289 AC: 10 AN: 3476

ClinVar

ClinVar submissions as Germline

Significance: Benign

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	-	4	not specified (4)
-	-	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	Cardiomyopathy (1)
-	-	1	Cardiovascular phenotype (1)
-	-	1	Early-onset myopathy with fatal cardiomyopathy (1)
-	-	1	Myopathy, myofibrillar, 9, with early respiratory failure (1)
-	-	1	not provided (2)
-	-	1	Tibial muscular dystrophy (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.62
BayesDel_addAF	Benign	-0.29	T
BayesDel_noAF	Benign	-0.18
CADD	Benign	22
DANN	Benign	0.93
Eigen	Uncertain	0.67
Eigen_PC	Pathogenic	0.69
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.91	D
MetaRNN	Benign	0.0078	T
MetaSVM	Uncertain	-0.26	T
PhyloP100		9.3
PrimateAI	Uncertain	0.68	T
PROVEAN	Uncertain	-3.9	D
REVEL	Uncertain	0.49
Sift	Benign	0.047	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.45
MVP		0.33
MPC		0.54
ClinPred		0.11	T
GERP RS		5.1
Mutation Taster		=91/9	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: rs562856820; hg19: chr2-179640716;