rs372716177

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 0P and 13B. BP4_StrongBP6BS1BS2

The NM_001267550.2(TTN):​c.102737G>A​(p.Arg34246His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000389 in 1,613,816 control chromosomes in the GnomAD database, including 5 homozygotes. In-silico tool predicts a benign outcome for this variant. 11/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00019 ( 1 hom., cov: 32)
Exomes 𝑓: 0.00041 ( 4 hom. )

Consequence

TTN
NM_001267550.2 missense

Scores

2
6
9

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:8

Conservation

PhyloP100: 7.88
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -13 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.008197546).
BP6
Variant 2-178533878-C-T is Benign according to our data. Variant chr2-178533878-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 47654.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=3, Benign=3, Uncertain_significance=2}. Variant chr2-178533878-C-T is described in Lovd as [Benign]. Variant chr2-178533878-C-T is described in Lovd as [Likely_benign].
BS1
Variant frequency is greater than expected in population sas. gnomad4 allele frequency = 0.00019 (29/152232) while in subpopulation SAS AF= 0.0027 (13/4816). AF 95% confidence interval is 0.0016. There are 1 homozygotes in gnomad4. There are 13 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.
BS2
High Homozygotes in GnomAdExome4 at 4 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTNNM_001267550.2 linkc.102737G>A p.Arg34246His missense_variant Exon 358 of 363 ENST00000589042.5 NP_001254479.2 A0A0A0MTS7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTNENST00000589042.5 linkc.102737G>A p.Arg34246His missense_variant Exon 358 of 363 5 NM_001267550.2 ENSP00000467141.1 A0A0A0MTS7

Frequencies

GnomAD3 genomes
AF:
0.000191
AC:
29
AN:
152114
Hom.:
1
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000196
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00270
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000132
Gnomad OTH
AF:
0.000480
GnomAD3 exomes
AF:
0.000755
AC:
188
AN:
248996
Hom.:
3
AF XY:
0.00105
AC XY:
142
AN XY:
135088
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000232
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00520
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000168
Gnomad OTH exome
AF:
0.000331
GnomAD4 exome
AF:
0.000409
AC:
598
AN:
1461584
Hom.:
4
Cov.:
39
AF XY:
0.000563
AC XY:
409
AN XY:
727074
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000201
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00493
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.000113
Gnomad4 OTH exome
AF:
0.000547
GnomAD4 genome
AF:
0.000190
AC:
29
AN:
152232
Hom.:
1
Cov.:
32
AF XY:
0.000175
AC XY:
13
AN XY:
74428
show subpopulations
Gnomad4 AFR
AF:
0.0000722
Gnomad4 AMR
AF:
0.000196
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00270
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.000132
Gnomad4 OTH
AF:
0.000475
Alfa
AF:
0.0000983
Hom.:
0
Bravo
AF:
0.0000869
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000122
AC:
1
ExAC
AF:
0.000803
AC:
97
Asia WGS
AF:
0.00231
AC:
8
AN:
3478
EpiCase
AF:
0.000109
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:8
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Uncertain:1Benign:2
-
Clinical Genetics, Academic Medical Center
Significance: Benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Apr 19, 2012
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The Arg31678His variant (TTN) has not been reported in the literature nor previo usly identified by our laboratory. Computational analyses (biochemical amino aci d properties, conservation, AlignGVGD, PolyPhen2, and SIFT) do not provide stron g support for or against an impact to the protein. This variant has been identif ied in 0.01% (1/6620) of European American chromosomes from a broad population b y the NHLBI Exome Sequencing Project (http://evs.gs.washington.edu/EVS/; dbSNP ) ; however, this frequency is too low to rule out a disease causing role. In summ ary, additional information is needed to fully assess the clinical significance of the Arg31678His variant. -

Jul 09, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not provided Benign:3
-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Jan 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

TTN: BS2 -

May 15, 2019
GeneDx
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant is associated with the following publications: (PMID: 24503780) -

Primary dilated cardiomyopathy Uncertain:1
-
Genetics and Genomics Program, Sidra Medicine
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: research

- -

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Benign:1
Jan 29, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Cardiomyopathy Benign:1
Nov 26, 2021
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Cardiovascular phenotype Benign:1
Dec 05, 2019
Ambry Genetics
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.28
BayesDel_addAF
Benign
-0.26
T
BayesDel_noAF
Benign
-0.14
CADD
Benign
22
DANN
Benign
0.93
Eigen
Uncertain
0.66
Eigen_PC
Pathogenic
0.70
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.95
D;D;D;.;D;D;D
M_CAP
Benign
0.035
D
MetaRNN
Benign
0.0082
T;T;T;T;T;T;T
MetaSVM
Benign
-0.38
T
MutationAssessor
Benign
0.0
.;.;.;N;.;.;N
PrimateAI
Uncertain
0.53
T
PROVEAN
Uncertain
-3.5
D;D;.;.;D;D;.
REVEL
Uncertain
0.42
Sift
Uncertain
0.0050
D;D;.;.;D;D;.
Polyphen
1.0
.;.;.;D;.;.;D
Vest4
0.38
MVP
0.36
MPC
0.51
ClinPred
0.11
T
GERP RS
5.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs372716177; hg19: chr2-179398605; COSMIC: COSV60109887; COSMIC: COSV60109887; API