19-55151892-C-G

Position:

• chr19-55151892-C-G

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Moderate PP5_Moderate

The NM_000363.5(TNNI3):​c.575G>C​(p.Arg192Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R192C) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TNNI3 NM_000363.5 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.32

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]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PM1: In a chain Troponin I, cardiac muscle (size 208) in uniprot entity TNNI3_HUMAN there are 86 pathogenic changes around while only 10 benign (90%) in NM_000363.5
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr19-55151893-G-A is described in Lovd as [Pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.926
• PP5: Variant 19-55151892-C-G is Pathogenic according to our data. Variant chr19-55151892-C-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 179536.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TNNI3	NM_000363.5	c.575G>C	p.Arg192Pro	missense_variant	8/8	ENST00000344887.10	NP_000354.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TNNI3	ENST00000344887.10	c.575G>C	p.Arg192Pro	missense_variant	8/8	1	NM_000363.5	ENSP00000341838	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hypertrophic cardiomyopathy Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Jul 13, 2016

The p.Arg192Pro variant in TNNI3 is absent from large population studies. This v ariant has been identified by our laboratory in 1 Caucasian infant with HCM. Par ental studies (performed by a different laboratory) revealed de novo occurrence. In addition, 3 other disease-causing variants at this position (p.Arg192His, p. Arg192Cys, and p.Arg192Leu) have been identified in multiple individuals with HC M and/or RCM and have occurred de novo in multiple cases, strongly supporting th at changes at this position may lead to disease (Mogensen 2003, Gomes 2005, Koba yashi 2006, Davis 2007, Mathur 2009, Rai 2009, Davis 2010, Millat 2010, van den Wijngaard 2011, Liu 2012, Yang 2013, LMM data). Computational prediction tools a nd conservation analysis do not provide additional support for or against an imp act to the protein. In summary, although additional studies are required to full y establish its clinical significance, the p.Arg192Pro variant is likely pathoge nic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
CardioboostCm	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.33
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.94	D;D
Eigen	Pathogenic	0.79
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.67	D
MetaRNN	Pathogenic	0.93	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.5	M;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.75	T
PROVEAN	Pathogenic	-6.5	D;.
REVEL	Pathogenic	0.93
Sift	Uncertain	0.0010	D;.
Sift4G	Pathogenic	0.0010	D;D
Polyphen		1.0	D;.
Vest4		0.85
MutPred		0.71		Loss of MoRF binding (P = 0.0019);.;
MVP		0.99
MPC		2.0
ClinPred		1.0	D
GERP RS		4.5
Varity_R		0.98

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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

Other links and lift over

dbSNP: rs104894729; hg19: chr19-55663260;