rs544241749

Variant names:

• chr2-178735502-G-A
• rs544241749
• NM_001267550.2:c.14935+9C>T

Variant summary

Our verdict is Benign. The variant received -12 ACMG points: 0P and 12B. BP4_Strong BP6_Very_Strong

The NM_001267550.2(TTN):​c.14935+9C>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000685 in 1,547,448 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 0.000046 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000071 (0 hom.)
• Consequence: TTN NM_001267550.2 intron
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:8
• Conservation: PhyloP100: -0.581
• Publications: 0 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 -12 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.88).
• BP6: Variant 2-178735502-G-A is Benign according to our data. Variant chr2-178735502-G-A is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 166222.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

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.14935+9C>T		intron	N/A	NP_001254479.2
	TTN	NM_001256850.1		c.13984+9C>T		intron	N/A	NP_001243779.1
	TTN	NM_133378.4		c.11203+9C>T		intron	N/A	NP_596869.4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTN	ENST00000589042.5	TSL:5 MANE Select	c.14935+9C>T		intron	N/A	ENSP00000467141.1
	TTN	ENST00000446966.2	TSL:1	c.14935+9C>T		intron	N/A	ENSP00000408004.2
	TTN	ENST00000436599.2	TSL:1	c.14659+9C>T		intron	N/A	ENSP00000405517.2

Frequencies

GnomAD3 genomes AF: 0.0000460 AC: 7 AN: 152202 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000965

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000131

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: 0.000478

GnomAD2 exomes AF: 0.0000210 AC: 4 AN: 190912 AF XY: 0.0000293

Gnomad AFR exome AF: 0.000138

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000649

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000108

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000710 AC: 99 AN: 1395128 Hom.: 0 Cov.: 29 AF XY: 0.0000668 AC XY: 46 AN XY: 688378

African (AFR) AF: 0.0000975 AC: 3 AN: 30762

American (AMR) AF: 0.00 AC: 0 AN: 32496

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 21982

East Asian (EAS) AF: 0.000128 AC: 5 AN: 39132

South Asian (SAS) AF: 0.0000276 AC: 2 AN: 72454

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 50464

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5318

European-Non Finnish (NFE) AF: 0.0000654 AC: 71 AN: 1085092

Other (OTH) AF: 0.000313 AC: 18 AN: 57428

GnomAD4 genome AF: 0.0000460 AC: 7 AN: 152320 Hom.: 0 Cov.: 33 AF XY: 0.0000537 AC XY: 4 AN XY: 74476

African (AFR) AF: 0.0000962 AC: 4 AN: 41572

American (AMR) AF: 0.000131 AC: 2 AN: 15300

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5178

South Asian (SAS) AF: 0.00 AC: 0 AN: 4832

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10616

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68030

Other (OTH) AF: 0.000473 AC: 1 AN: 2114

Alfa AF: 0.0000334 Hom.: 0

Bravo AF: 0.0000151

Asia WGS AF: 0.00375 AC: 13 AN: 3478

ClinVar

ClinVar submissions as Germline

Significance: Benign/Likely benign

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	-	3	not specified (3)
-	-	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	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
BayesDel_noAF	Benign	-0.88
CADD	Benign	3.6
DANN	Benign	0.62
PhyloP100		-0.58
Mutation Taster		=100/0	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: rs544241749; hg19: chr2-179600229;