chr17-39666078-G-C

Variant names:

• chr17-39666078-G-C
• rs397516864
• NM_003673.4:c.473G>C

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PM5 PP3_Moderate

The NM_003673.4(TCAP):​c.473G>C​(p.Arg158Pro) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R158C) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TCAP NM_003673.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.82
• Publications: 0 publications found

Genes affected

TCAP (HGNC:11610): (titin-cap) Sarcomere assembly is regulated by the muscle protein titin. Titin is a giant elastic protein with kinase activity that extends half the length of a sarcomere. It serves as a scaffold to which myofibrils and other muscle related proteins are attached. This gene encodes a protein found in striated and cardiac muscle that binds to the titin Z1-Z2 domains and is a substrate of titin kinase, interactions thought to be critical to sarcomere assembly. Mutations in this gene are associated with limb-girdle muscular dystrophy type 2G. [provided by RefSeq, Jul 2008]

TCAP Gene-Disease associations (from GenCC):

• autosomal recessive limb-girdle muscular dystrophy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• hypertrophic cardiomyopathy 25

  Inheritance: AD Classification: STRONG, MODERATE, LIMITED Submitted by: Ambry Genetics, PanelApp Australia, Labcorp Genetics (formerly Invitae)
• autosomal recessive limb-girdle muscular dystrophy type 2G

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• dilated cardiomyopathy

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• hypertrophic cardiomyopathy

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

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

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-39666077-C-T is described in CliVar as Conflicting_classifications_of_pathogenicity. Clinvar id is 239547.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.845

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TCAP	NM_003673.4	c.473G>C	p.Arg158Pro	missense_variant	Exon 2 of 2	ENST00000309889.3	NP_003664.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TCAP	ENST00000309889.3	c.473G>C	p.Arg158Pro	missense_variant	Exon 2 of 2	1	NM_003673.4	ENSP00000312624.2
TCAP	ENST00000578283.1	c.401G>C	p.Arg134Pro	missense_variant	Exon 3 of 3	5		ENSP00000462787.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.65
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.37
CADD	Pathogenic	31
DANN	Benign	0.94
DEOGEN2	Pathogenic	0.86	D;.
Eigen	Pathogenic	0.68
Eigen_PC	Pathogenic	0.74
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Benign	0.83	T;T
M_CAP	Pathogenic	0.58	D
MetaRNN	Pathogenic	0.84	D;D
MetaSVM	Uncertain	0.58	D
MutationAssessor	Uncertain	2.2	M;.
PhyloP100		6.8
PrimateAI	Uncertain	0.69	T
PROVEAN	Pathogenic	-4.5	D;.
REVEL	Pathogenic	0.83
Sift	Pathogenic	0.0	D;.
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;.
Vest4		0.65
MutPred		0.55		Loss of helix (P = 0.0076);.;
MVP		0.99
MPC		1.1
ClinPred		0.99	D
GERP RS		5.8
Varity_R		0.93
gMVP		0.52
Mutation Taster		=17/83	disease causing

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

Other links and lift over

dbSNP: rs397516864; hg19: chr17-37822331;