chr19-55154172-C-T

Variant names:

• chr19-55154172-C-T
• rs730881069
• NM_000363.5:c.407G>A

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PP3 PP5

The NM_000363.5(TNNI3):​c.407G>A​(p.Arg136Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,460,818 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. R136P) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: TNNI3 NM_000363.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:10 U:2
• Conservation: PhyloP100: 1.20
• Publications: 10 publications found

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]

TNNI3 Gene-Disease associations (from GenCC):

• hypertrophic cardiomyopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• hypertrophic cardiomyopathy 7

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• dilated cardiomyopathy 2A

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• cardiomyopathy, familial restrictive, 1

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• dilated cardiomyopathy 1FF

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• dilated cardiomyopathy

  Inheritance: AR, AD Classification: STRONG Submitted by: ClinGen
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial isolated restrictive cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• arrhythmogenic right ventricular cardiomyopathy

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 17 uncertain in NM_000363.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 19-55154172-C-T is Pathogenic according to our data. Variant chr19-55154172-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 181576.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000363.5. 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
	TNNI3	NM_000363.5	MANE Select	c.407G>A	p.Arg136Gln	missense	Exon 7 of 8	NP_000354.4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TNNI3	ENST00000344887.10	TSL:1 MANE Select	c.407G>A	p.Arg136Gln	missense	Exon 7 of 8	ENSP00000341838.5	P19429
	TNNI3	ENST00000665070.1		c.440G>A	p.Arg147Gln	missense	Exon 7 of 8	ENSP00000499482.1	A0A590UJN1
	TNNI3	ENST00000714238.1		c.395G>A	p.Arg132Gln	missense	Exon 7 of 8	ENSP00000519518.1	A0AAQ5BHR0

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD2 exomes AF: 0.00000402 AC: 1 AN: 248592 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000883

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1460818 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 726706

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.0000232 AC: 2 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52364

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112002

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 31

Alfa AF: 0.00 Hom.: 0

ExAC AF: 0.00000827 AC: 1

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
3	1	-	Hypertrophic cardiomyopathy 7 (4)
3	-	-	not provided (3)
1	1	-	Hypertrophic cardiomyopathy (2)
1	-	-	Cardiomyopathy (1)
1	-	-	Cardiovascular phenotype (1)
1	-	-	TNNI3-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.19
CardioboostCm	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.23	D
BayesDel_noAF	Uncertain	0.10
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.90	D
Eigen	Uncertain	0.28
Eigen_PC	Uncertain	0.24
FATHMM_MKL	Benign	0.45	N
LIST_S2	Pathogenic	0.98	D
M_CAP	Uncertain	0.24	D
MetaRNN	Uncertain	0.68	D
MetaSVM	Pathogenic	0.82	D
MutationAssessor	Benign	1.9	L
PhyloP100		1.2
PrimateAI	Uncertain	0.63	T
PROVEAN	Benign	-2.2	N
REVEL	Uncertain	0.60
Sift	Benign	0.094	T
Sift4G	Benign	0.13	T
Polyphen		1.0	D
Vest4		0.58
MutPred		0.63		Loss of methylation at R136 (P = 0.0197)
MVP		0.93
MPC		1.6
ClinPred		0.88	D
GERP RS		4.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.63
Mutation Taster		=14/86	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.63		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.63		Position offset: -3

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs730881069; hg19: chr19-55665540; COSMIC: COSV52572523; COSMIC: COSV52572523;