rs727504529

Variant names:

• chr2-178590909-C-T
• rs727504529
• NM_001267550.2:c.60816G>A

Variant summary

Our verdict is Benign. The variant received -11 ACMG points: 0P and 11B. BP4_Moderate BP6_Very_Strong BP7

The NM_001267550.2(TTN):​c.60816G>A​(p.Pro20272Pro) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000223 in 1,612,174 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 Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000024 (0 hom.)
• Consequence: TTN NM_001267550.2 synonymous
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:4
• Conservation: PhyloP100: 0.538
• Publications: 2 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 -11 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.31).
• BP6: Variant 2-178590909-C-T is Benign according to our data. Variant chr2-178590909-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 178906.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=0.538 with no splicing effect.

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.60816G>A	p.Pro20272Pro	synonymous	Exon 304 of 363	NP_001254479.2	Q8WZ42-12
	TTN	NM_001256850.1		c.55893G>A	p.Pro18631Pro	synonymous	Exon 254 of 313	NP_001243779.1	Q8WZ42-1
	TTN	NM_133378.4		c.53112G>A	p.Pro17704Pro	synonymous	Exon 253 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.60816G>A	p.Pro20272Pro	synonymous	Exon 304 of 363	ENSP00000467141.1	Q8WZ42-12
	TTN	ENST00000446966.2	TSL:1	c.60660G>A	p.Pro20220Pro	synonymous	Exon 302 of 361	ENSP00000408004.2	A0A1B0GXE3
	TTN	ENST00000436599.2	TSL:1	c.60540G>A	p.Pro20180Pro	synonymous	Exon 302 of 361	ENSP00000405517.2	A0A0C4DG59

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 152016 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: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000484 AC: 12 AN: 247818 AF XY: 0.0000595

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.000300

Gnomad EAS exome AF: 0.0000559

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000179

Gnomad OTH exome AF: 0.000666

GnomAD4 exome AF: 0.0000240 AC: 35 AN: 1460158 Hom.: 0 Cov.: 35 AF XY: 0.0000317 AC XY: 23 AN XY: 726150

African (AFR) AF: 0.0000299 AC: 1 AN: 33426

American (AMR) AF: 0.00 AC: 0 AN: 44692

Ashkenazi Jewish (ASJ) AF: 0.000230 AC: 6 AN: 26096

East Asian (EAS) AF: 0.000101 AC: 4 AN: 39612

South Asian (SAS) AF: 0.0000232 AC: 2 AN: 86172

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53374

Middle Eastern (MID) AF: 0.00139 AC: 8 AN: 5748

European-Non Finnish (NFE) AF: 0.0000108 AC: 12 AN: 1110722

Other (OTH) AF: 0.0000332 AC: 2 AN: 60316

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 152016 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74238

African (AFR) AF: 0.0000241 AC: 1 AN: 41412

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

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5156

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: 0.00 AC: 0 AN: 67972

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

Alfa AF: 0.000240 Hom.: 0

Bravo AF: 0.0000264

ClinVar

ClinVar submissions

Significance: Likely benign

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	-	1	Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G (1)
-	-	1	Cardiovascular phenotype (1)
-	-	1	not provided (1)
-	-	1	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.31
CADD	Benign	7.7
DANN	Benign	0.77
PhyloP100		0.54
Mutation Taster		=85/15	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: rs727504529; hg19: chr2-179455636; COSMIC: COSV60052534; COSMIC: COSV60052534;