rs368861241

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1PM5PP3_ModeratePP5

The NM_000363.5(TNNI3):​c.484C>T​(p.Arg162Trp) variant causes a missense change. The variant allele was found at a frequency of 0.0000229 in 1,612,806 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. R162P) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000025 ( 0 hom. )

Consequence

TNNI3
NM_000363.5 missense

Scores

9
8
3

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:17U:3

Conservation

PhyloP100: 3.73
Variant links:
Genes affected
TNNI3 (HGNC:11947): (troponin I3, cardiac type) Troponin I (TnI), along with troponin T (TnT) and troponin C (TnC), is one of 3 subunits that form the troponin complex of the thin filaments of striated muscle. TnI is the inhibitory subunit; blocking actin-myosin interactions and thereby mediating striated muscle relaxation. The TnI subfamily contains three genes: TnI-skeletal-fast-twitch, TnI-skeletal-slow-twitch, and TnI-cardiac. This gene encodes the TnI-cardiac protein and is exclusively expressed in cardiac muscle tissues. Mutations in this gene cause familial hypertrophic cardiomyopathy type 7 (CMH7) and familial restrictive cardiomyopathy (RCM). Troponin I is useful in making a diagnosis of heart failure, and of ischemic heart disease. An elevated level of troponin is also now used as indicator of acute myocardial injury in patients hospitalized with moderate/severe Coronavirus Disease 2019 (COVID-19). Such elevation has also been associated with higher risk of mortality in cardiovascular disease patients hospitalized due to COVID-19. [provided by RefSeq, Aug 2020]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PM1
In a helix (size 2) in uniprot entity TNNI3_HUMAN there are 6 pathogenic changes around while only 0 benign (100%) in NM_000363.5
PM5
Other missense variant is known to change same aminoacid residue: Variant chr19-55154094-C-G is described in Lovd as [Pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.883
PP5
Variant 19-55154095-G-A is Pathogenic according to our data. Variant chr19-55154095-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 161396.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=11, Pathogenic=4, Uncertain_significance=3}. Variant chr19-55154095-G-A is described in Lovd as [Pathogenic]. Variant chr19-55154095-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TNNI3NM_000363.5 linkc.484C>T p.Arg162Trp missense_variant Exon 7 of 8 ENST00000344887.10 NP_000354.4 P19429Q6FGX2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TNNI3ENST00000344887.10 linkc.484C>T p.Arg162Trp missense_variant Exon 7 of 8 1 NM_000363.5 ENSP00000341838.5 P19429

Frequencies

GnomAD3 genomes
AF:
0.00000659
AC:
1
AN:
151844
Hom.:
0
Cov.:
31
show subpopulations
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:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000402
AC:
10
AN:
249000
Hom.:
0
AF XY:
0.0000444
AC XY:
6
AN XY:
135190
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000290
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000167
Gnomad SAS exome
AF:
0.0000980
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000265
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000246
AC:
36
AN:
1460962
Hom.:
0
Cov.:
32
AF XY:
0.0000303
AC XY:
22
AN XY:
726840
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.000139
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000198
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000659
AC:
1
AN:
151844
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
74126
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000120
AC:
1
ExAC
AF:
0.0000331
AC:
4
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:17Uncertain:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Hypertrophic cardiomyopathy 7 Pathogenic:5Uncertain:2
-
Juno Genomics, Hangzhou Juno Genomics, Inc
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

PM2_Supporting+PS4_Moderate+PS3_Supporting+PM1 -

Apr 01, 2023
Clinical Laboratory Sciences Program (CLSP), King Saud bin Abdulaziz University for Health Sciences (KSAU-HS)
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Jan 04, 2025
Genomic Medicine Center of Excellence, King Faisal Specialist Hospital and Research Centre
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Dec 03, 2018
Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: research

The heterozygous p.Arg162Trp variant in TNNI3 was identified by our study in one individual with hypertrophic cardiomyopathy. This variant has been identified in 0.004071% (10/245660) of chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP rs368861241). Please note that for diseases like hypertrophic cardiomyopathy with clinical variability, or reduced penetrance, pathogenic variants may be present at a low frequency in the general population. This variant has been reported likely pathogenic or pathogenic in ClinVar (Variation ID: 161396). Two additional missense variants that affect the Arginine (Arg) at position 162 have been reported likely pathogenic or pathogenic in ClinVar, suggesting that a change in this position would not be tolerated (Variation ID: 43390, 43389). The p.Arg162Trp variant in TNNI3 has been reported in 12 individuals (6 Middle Eastern, 6 unknown) and segregated with disease in the homozygous state in 4 affected relatives from 2 families. The 6 clinically unaffected individuals from these 2 families were heterozygous for the variant, though this disease is known to have clinical variability (PMID: 24113344, 23270746). Four additional, unrelated individuals with this variant and hypertrophic cardiomyopathy have been reported in the literature (PMID: 22429680, 21799269). Computational prediction tools and conservation analyses suggest that this variant may impact the protein, though this information is not predictive enough to determine pathogenicity. In vitro functional studies provide some evidence that the p.Arg162Trp variant may impact protein function by reducing inhibition of actin-tropomyosin-activated myosin ATPase and increased calcium sensitivity in enzyme activity regulation (PMID: 11735257, 10806205). However, these types of assays may not accurately represent biological function. In summary, although additional studies are required to fully establish its clinical significance, this variant is likely pathogenic. ACMG/AMP Criteria applied: PP1, PP3, PM2, PM5, PS3_Supporting (Richards 2015). -

Jan 30, 2018
Human Genome Sequencing Center Clinical Lab, Baylor College of Medicine
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This c.484C>T (p.Arg162Trp) variant in the TNNI3 gene has been reported in multiple HCM patients with significantly higher prevalence [PMID: 9241277,21799269,21896538,22429680] than that observed as extremely low in general population according to gnomad database. Arginine at amino acid position 162 is highly conserved during evolution. Other amino acid changes at this or nearby positions have been reported in HCM patients as deleterious mutations [PMID: 27385602, 12860912, 21310275, 25611685, 27532257]. Functional studies showed that this mutant causes increased calcium sensitivity of cardiac muscle contraction and other alterations [PMID: 11735257, 10806205]. Homozygotes of this variant have been observed in two affected siblings with HCM while heterozygous carriers in this family are all normal. Multiple in silico predictions suggest this arginine to histidine change is deleterious. Based upon above evidences, this c.484C>T (p.Arg162Trp) variant in the TNNI3 gene is classified as pathogenic. -

Dec 20, 2024
Clinical Genetics Laboratory, Region Ostergotland
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The variant NM_000363.5(TNNI3):c.484C>T, p.(Arg162Trp) has been assessed using the ClinGen Cardiomyopathy Expert Panel Specifications to the ACMG/AMP Variant Interpretation Guidelines for TNNI3 Version 1.0.0 Based on this information, the following ACMG/AMP criteria were applied in classifying this variant: PM1 -

Oct 19, 2020
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as 3A-VUS. Following criteria are met: 0103 - Both loss-of function and gain-of-function are known mechanisms of disease for this gene and are associated with hypertrophic cardiomyopathy 7 (HCM; MIM#613690). Missense have variants been functionally proven to cause both mechanisms (PMID: 21533915). (I) 0108 - This gene is known to be associated with both recessive and dominant disease. The recessive form of inheritance is the exception and has only been reported in two families (PMIDs: 15070570, 23270746). (I) 0112 - Variants in this gene are known to have reduced penetrance (PMID: 15607392). (I) 0115 - Variants in this gene are known to have variable expressivity (PMID: 23270746). (I) 0200 - Variant is predicted to result in a missense amino acid change from arginine to tryptophan. (I) 0251 - This variant is heterozygous. (I) 0302 - Variant is present in gnomAD (v2) <0.001 for a dominant condition (10 heterozygotes, 0 homozygotes). (SP) 0309 - An alternative amino acid change at the same position has been observed in gnomAD (v2) (10 heterozygote, 0 homozygotes). (I) 0502 - Missense variant with conflicting in silico predictions and uninformative conservation. (I) 0600 - Variant is located in the annotated troponin domain (NCBI, PDB, DECIPHER). (I) 0701 - Other missense variants comparable to the one identified in this case have strong previous evidence for pathogenicity. Three alternative changes in this same residue, p.(Arg162Pro), p.(Arg162Gln) and p.(Arg162Leu), have been reported in multiple individuals with HCM (ClinVar, PMID: 32686758). (SP) 0808 - Previous reports of pathogenicity for this variant are conflicting. Even though there are reports in the literature that classify this variant as a variant of uncertain significance (VUS) (DECIPHER, PMID: 27532257), it has been reported as likely pathogenic and pathogenic in multiple individuals with HCM (ClinVar, PMIDs: 32830170, 32686758, 28420666). It has also been reported in families with autosomal recessive inheritance, with unaffected heterozygote carriers (ClinVar, PMID: 23270746). (I) 1002 - This variant has moderate functional evidence supporting abnormal protein function. In vitro studies show that mutant reduced ability to inhibit actin-TM-activated myosin ATPase and increased calcium sensitivity of ATPase regulation, suggesting that this mutation may result in relaxation abnormalities rather than contraction as other mutants reported in HCM. In addition, the mutant has an increased affinity for TnC (PMID: 10806205). (SP) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Hypertrophic cardiomyopathy Pathogenic:5
Mar 23, 2020
Agnes Ginges Centre for Molecular Cardiology, Centenary Institute
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: research

TNNI3 p.Arg162Trp was identified as a homozygous variant in 1 HCM proband as part of our research program. The proband came from a consanguineous family of Middle Eastern descent. An affected sibling was also found to have this homozygous variant. For further information please feel free to contact us. -

Jan 29, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 162 of the TNNI3 protein (p.Arg162Trp). This variant is present in population databases (rs368861241, gnomAD 0.02%). This missense change has been observed in individuals with hypertrophic cardiomyopathy, in the heterozygous and homozygous states (PMID: 9241277, 21799269, 21896538, 22429680, 25132132, 27532257, 28356264, 30847666, 32746448, 33673806). ClinVar contains an entry for this variant (Variation ID: 161396). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. Experimental studies have shown that this missense change affects TNNI3 function (PMID: 10806205, 11735257). This variant disrupts the p.Arg162 amino acid residue in TNNI3. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 12860912, 15607392, 15698845, 15992656, 16352453, 22876777). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Jan 06, 2024
All of Us Research Program, National Institutes of Health
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This missense variant replaces arginine with tryptophan at codon 162 of the TNNI3 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). Functional studies have shown that this variant increases the Ca2+ sensitivity of cardiac muscle contraction (PMID: 10806205, 11735257). This variant has been reported in over ten individuals affected with hypertrophic cardiomyopathy (PMID: 9241277, 21799269, 21896538, 22429680, 24113344, 27532257, 30105547, 30847666, 32746448, 33495596, 33495597, 33673806). In one family, this variant was observed in homozygosity in two siblings affected with hypertrophic cardiomyopathy (PMID: 24113344). However, four heterozygous carriers from this family were not clinically affected. This variant has been identified in 10/249000 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Different missense variants occurring at this codon, p.Arg162Pro and p.Arg162Gln, are considered to be disease-causing (ClinVar variant ID: 43390 and 43389), suggesting that arginine at this position is important for TNNI3 protein function. Based on the available evidence, this variant is classified as Likely Pathogenic. -

Jun 17, 2020
Human Genome Sequencing Center Clinical Lab, Baylor College of Medicine
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The c.484C>T (p.Arg162Trp) variant in the TNNI3 gene is located on the exon 7 and is predicted to replace arginine with tryptophan at codon 162 (p.Arg162Trp). The variant has been reported in more than 10 unrelated individuals affected with hypertrophic cardiomyopathy (PMID: 30105547, 32830170, 21799269, 9241277, 21896538, 28356264, 22429680, 27532257, 23270746). Alternative variants disrupting the same amino acid (p.Arg162Gln, p.Arg162Pro) have been interpreted as likely pathogenic or pathogenic in ClinVar (ID: 43389, 43390). In vitro experimental studies show evidence for a negative functional impact of the p.Arg162Trp variant (PMID: 10806205, 11735257). This variant is rare in the general population according to gnomAD (10/249000). Therefore, the c.484C>T (p.Arg162Trp) variant of TNNI3 has been classified as likely pathogenic. -

Oct 08, 2020
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.Arg162Trp variant in TNNI3 has been reported in the heterozygous state in >10 individuals with hypertrophic cardiomyopathy (HCM; Kimura 1997 PMID: 9241277; Garcia-Pavia 2011 PMID: 21896538; Kubo 2011 PMID: 21799269; Gomez 2017 PMID: 28356264; Walsh 2017 PMID: 27532257; LMM data). It was also identified in the homozygous state in 1 Indian and 1 Jordanian individuals with HCM and segregated with disease in the homozygous state in 3 affected relatives, but none of the heterozygous relatives (<50 years old) were affected (Gray 2013 PMID: 23270746; Das 2014 PMID: 24113344; LMM data). The variant has also been reported by other clinical laboratories in ClinVar (Variation ID: 161396) and was identified in 0.003% (3/113182) of European chromosomes and 0.02% (3/17978) of East Asian chromosomes by gnomAD (http://gnomad.broadinstitute.org). In vitro functional studies provide some evidence that the p.Arg162Trp variant may impact protein function (Elliott 2000 PMID: 10806205; Takahashi-Yanaga 2001 PMID: 11735257). Computational prediction tools and conservation analysis do not provide strong support for or against an impact to the protein. Moreover, two other variants have been identified at this position (p.Arg162Pro, p.Arg162Gln) and have been classified by this laboratory as likely pathogenic, suggesting changes at this position are not tolerated. The available data on the p.Arg162Gln suggests that it may be a mild variant, with reduced penetrance. In summary, the p.Arg162Trp variant is likely pathogenic; however, this variant may have a milder role suggested by the incomplete penetrance seen in some family members and the individuals who were homozygous, similar to that observed for p.Arg162Gln. ACMG/AMP Criteria applied: PS4_Moderate, PM2_Supporting, PM5_Supporting, PP1, PS3_Supporting. -

Cardiomyopathy Pathogenic:2
Jan 24, 2023
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

May 09, 2023
Color Diagnostics, LLC DBA Color Health
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This missense variant replaces arginine with tryptophan at codon 162 of the TNNI3 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). Functional studies have shown that this variant increases the Ca2+ sensitivity of cardiac muscle contraction (PMID: 10806205, 11735257). This variant has been reported in over ten individuals affected with hypertrophic cardiomyopathy (PMID: 9241277, 21799269, 21896538, 22429680, 24113344, 27532257, 30105547, 30847666, 32746448, 33495596, 33495597, 33673806). In one family, this variant was observed in homozygosity in two siblings affected with hypertrophic cardiomyopathy (PMID: 24113344). However, four heterozygous carriers from this family were not clinically affected. This variant has been identified in 10/249000 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Different missense variants occurring at this codon, p.Arg162Pro and p.Arg162Gln, are considered to be disease-causing (ClinVar variant ID: 43390 and 43389), suggesting that arginine at this position is important for TNNI3 protein function. Based on the available evidence, this variant is classified as Likely Pathogenic. -

not provided Pathogenic:2
Apr 25, 2022
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Reported in the homozygous state in both a proband with HCM with features of a restrictive process and her brother with classic HCM; autosomal recessive inheritance was proposed as the four individuals heterozygous for the variant (both parents and two siblings) were clinically unaffected (Gray et al., 2013); Published functional studies demonstrate that this variant interferes with normal troponin function and is expected to impair cardiac muscle relaxation (Elliott et al., 2000; Takahashi-Yanaga et al., 2001); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 23299917, 24113344, 20298698, 20350521, 25351510, 15992656, 29551499, 29203298, 11735257, 23270746, 25637381, 10615387, 23840593, 25342278, 21967901, 22429680, 21839045, 21799269, 9241277, 27532257, 25649125, 15607392, 22876777, 15698845, 15070570, 25132132, 30105547, 32686758, 32830170, 28356264, 32746448, 33673806, 30847666, 31447099, 21896538, 10806205, 33487615) -

Jul 01, 2024
CeGaT Center for Human Genetics Tuebingen
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

TNNI3: PM1, PM5, PS4:Moderate, PM2:Supporting, PS3:Supporting -

Cardiovascular phenotype Pathogenic:2
Nov 05, 2024
Ambry Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.R162W variant (also known as c.484C>T), located in coding exon 7 of the TNNI3 gene, results from a C to T substitution at nucleotide position 484. The arginine at codon 162 is replaced by tryptophan, an amino acid with dissimilar properties. This variant has been reported in the heterozygous state in multiple individuals with hypertrophic cardiomyopathy (HCM) (Kimura A et al. Nat. Genet. 1997;16:379-82; Garcia-Pavia P et al. Eur. J. Heart Fail. 2011;13:1193-201; Santos S et al. BMC Med. Genet. 2012;13:17; G&oacute;mez J et al. Circ. J. 2014;78:2963-71 Lopes LR et al. Heart. 2015;101:294-301; Walsh R et al. Genet. Med. 2017;19:192-203). This alteration has also been detected in a pediatric cardiomyopathy cohort It has also been detected in the homozygous state in two siblings and a third, unrelated individual with HCM; however, their heterozygous relatives were unaffected (Das K J et al. Genet. Med. 2014;16:286-93; Gray B et al. Int. J. Cardiol. 2013;168:1530-1). This variant has also been seen in an exome cohort, but cardiovascular history was not provided (Amendola LM et al. Genome Res. 2015;25:305-15). Functional studies suggest that this alteration impacts TNNI3 protein function (Elliott K et al. J. Biol. Chem. 2000;275:22069-74; Takahashi-Yanaga F et al. J. Mol. Cell. Cardiol. 2001;33:2095-107). Another variant at the same codon, p.R162Q (c.485G>A), has been described in association with HCM (Van Driest SL et al. Circulation. 2003;108(4):445-51). This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on the supporting evidence, this variant is expected to be causative of autosomal dominant TNNI3-related cardiomyopathy; however, its clinical significance for autosomal recessive TNNI3-related dilated cardiomyopathy is unclear. -

Jul 27, 2018
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: TNNI3 c.484C>T (p.Arg162Trp) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function and a different missense mutation at this same residue (p.Arg162Gln) has been internally classified as Likely Pathogenic, suggesting that changes at Arg162 are not tolerated. Additionally, several functional studies indicate that this variant reduces the apparent affinity of cTnI for actin without changing the intrinsic inhibitory activity, and induces a definite increase in the Ca2+- sensitivitiy of myofibrillar ATPase activity and force generation in skinned muscle fibers. It has been suggested that the decreased inhibition and increased calcium sensitivity may cause HCM via impaired relaxation rather than the impaired contraction seen with some other classes of HCM mutants (Elliott_2000). The variant allele was found at a frequency of 4e-05 in 247390 control chromosomes. This frequency is not significantly higher than expected for a pathogenic variant in LMM reportedly detected the variant in 4 individuals with HCM (1 Caucasian adult, 2 Indian adolescents, and 1 Jordanian adolescent). Several reported HCM patients in the literature (Kimura_1997, Garcia-Pavia_ 2011, Wang_2014, etc), and two individuals reported by LMM laboratory, were all heterozygous for the variant of interest, which is consistent with dominant inheritance. However, the variant has also been reported in two non-Caucasian families (one Indian and one Jordanian reported by LMM) and one Middle Eastern family (Gray_TNNI3_Int J Cardiol_2013) with 5 affected individuals being homozygous from the 3 families and none of the heterozygous family members being affected. This may suggest that c.484C>T is either a mild variant with reduced penetrance, and/or co-dominant effect is required to develop clinical features; recessive mode of inheritance cannot be completely ruled out. Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Hypertrophic cardiomyopathy 7;C1861861:Cardiomyopathy, familial restrictive, 1;C2678474:Dilated cardiomyopathy 2A;C2750091:Dilated cardiomyopathy 1FF Pathogenic:1
Aug 14, 2021
Fulgent Genetics, Fulgent Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Primary familial hypertrophic cardiomyopathy Uncertain:1
Jun 01, 2014
CSER _CC_NCGL, University of Washington
Significance: Uncertain significance
Review Status: flagged submission
Collection Method: research

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.41
CardioboostCm
Uncertain
0.64
BayesDel_addAF
Benign
-0.055
T
BayesDel_noAF
Uncertain
-0.050
CADD
Pathogenic
26
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.94
D;D
Eigen
Uncertain
0.34
Eigen_PC
Uncertain
0.34
FATHMM_MKL
Uncertain
0.81
D
LIST_S2
Pathogenic
0.97
D;D
M_CAP
Pathogenic
0.46
D
MetaRNN
Pathogenic
0.88
D;D
MetaSVM
Uncertain
0.50
D
MutationAssessor
Benign
1.4
L;.
PrimateAI
Uncertain
0.67
T
PROVEAN
Pathogenic
-4.9
D;.
REVEL
Pathogenic
0.67
Sift
Pathogenic
0.0
D;.
Sift4G
Pathogenic
0.0
D;D
Polyphen
1.0
D;.
Vest4
0.80
MVP
0.95
MPC
1.6
ClinPred
0.73
D
GERP RS
3.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.81

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: rs368861241; hg19: chr19-55665463; API