2-178531487-C-T
Variant summary
Our verdict is Likely benign. Variant got -1 ACMG points: 1P and 2B. PP2BP4_Moderate
The NM_001267550.2(TTN):c.105128G>A(p.Arg35043His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000239 in 1,613,846 control chromosomes in the GnomAD database, with no homozygous occurrence. 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). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R35043C) has been classified as Likely benign.
Frequency
Consequence
NM_001267550.2 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_benign. Variant got -1 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | MANE | UniProt |
---|---|---|---|---|---|---|---|
TTN | NM_001267550.2 | c.105128G>A | p.Arg35043His | missense_variant | 358/363 | ENST00000589042.5 | |
TTN-AS1 | NR_038272.1 | n.220-4245C>T | intron_variant, non_coding_transcript_variant |
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | TSL | MANE | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|
TTN | ENST00000589042.5 | c.105128G>A | p.Arg35043His | missense_variant | 358/363 | 5 | NM_001267550.2 | P1 | |
TTN-AS1 | ENST00000659121.1 | n.416+7851C>T | intron_variant, non_coding_transcript_variant |
Frequencies
GnomAD3 genomes AF: 0.000177 AC: 27AN: 152174Hom.: 0 Cov.: 32
GnomAD3 exomes AF: 0.000177 AC: 44AN: 248978Hom.: 0 AF XY: 0.000170 AC XY: 23AN XY: 135082
GnomAD4 exome AF: 0.000246 AC: 359AN: 1461554Hom.: 0 Cov.: 41 AF XY: 0.000235 AC XY: 171AN XY: 727088
GnomAD4 genome AF: 0.000177 AC: 27AN: 152292Hom.: 0 Cov.: 32 AF XY: 0.000161 AC XY: 12AN XY: 74470
ClinVar
Submissions by phenotype
not provided Uncertain:3
Uncertain significance, criteria provided, single submitter | clinical testing | Revvity Omics, Revvity | Sep 27, 2023 | - - |
Uncertain significance, criteria provided, single submitter | research | Biesecker Lab/Clinical Genomics Section, National Institutes of Health | Jun 24, 2013 | - - |
Uncertain significance, criteria provided, single submitter | clinical testing | Eurofins Ntd Llc (ga) | Feb 27, 2018 | - - |
not specified Uncertain:1
Uncertain significance, criteria provided, single submitter | clinical testing | GeneDx | Apr 02, 2015 | Missense variants in the TTN gene are considered 'unclassified' if they are not previously reported in the literature and do not have >1% frequency in the population to be considered a polymorphism. Research indicates that truncating mutations in the TTN gene are expected to account for approximately 25% of familial and 18% of sporadic idiopathic DCM; however, truncating variants in the TTN gene have been reported in approximately 3% of reported control alleles. There has been little investigation into non-truncating variants. (Herman D et al. Truncations of titin causing dilated cardiomyopathy. N Eng J Med 366:619-628, 2012) The variant is found in DCM-CRDM panel(s). - |
Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1
Uncertain significance, criteria provided, single submitter | clinical testing | Invitae | Aug 29, 2017 | - - |
Tip-toe gait Uncertain:1
Uncertain significance, criteria provided, single submitter | clinical testing | Practice for Gait Abnormalities, David Pomarino, Competency Network Toe Walking c/o Practice Pomarino | Nov 12, 2020 | Myopathy refers to diseases that affect skeletal Muscles. These diseases attack muscle fibers, making muscles weak. Inherited myopathies are often caused by inheriting an abnormal gene mutation from a parent that causes the disease. Symptoms of congenital myopathies usually start at birth or in early childhood, but may not appear until the teen years or even later in adulthood. Congenital myopathies are somewhat unique compared with other inherited myopathies, as weakness typically affects all muscles and is often not progressive. Symptoms are: Muscle weakness, most commonly of upper arms and shoulders and thighs, muscle cramps, stiffness and spasms, fatigue with exertion and lack of energy. Our patients all walk on tiptoe, so they show similar symptoms. When we genetically test them with our toe walking panel, we find that around 90 per cent of them have a genetic variant that explains their toe walking. These can be assigned, for example, to the area of myopathies (such as variants of the COL6A3 gene), the area of hereditary neuropathies (such as variants of the KMT2C gene) or the area of metabolic diseases (such as variants of the PYGM gene). In a smaller group of patients with almost identical symptoms, no abnormality is found in the genes of our panel, but spastic paraplegia can be detected. In another small group of our toe walkers, no abnormalities can be detected in the genes analysed in our toe walking panel, nor do they suffer from spastic paraplegia, as is also the case with healthy children. In contrast to these, however, they show a tiptoe gait. These patients suffer from infantile cerebral palsy, in which toe walking can also be observed. - |
Cardiovascular phenotype Benign:1
Likely benign, criteria provided, single submitter | clinical testing | Ambry Genetics | Jul 15, 2019 | 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:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at