rs387907216

chr19-49168301-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PP3 PP5

The NM_017636.4(TRPM4):c.490C>T(p.Arg164Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000547 in 1,461,830 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. R164Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 30)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: TRPM4 NM_017636.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:1
• Conservation: PhyloP100: 0.346

Genes affected

TRPM4 (HGNC:17993): (transient receptor potential cation channel subfamily M member 4) The protein encoded by this gene is a calcium-activated nonselective ion channel that mediates transport of monovalent cations across membranes, thereby depolarizing the membrane. The activity of the encoded protein increases with increasing intracellular calcium concentration, but this channel does not transport calcium. [provided by RefSeq, Mar 2016]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PP3: MetaRNN computational evidence supports a deleterious effect, 0.81
• PP5: Variant 19-49168301-C-T is Pathogenic according to our data. Variant chr19-49168301-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 35488.We mark this variant Likely_pathogenic, oryginal submissions are: {Pathogenic=1, Uncertain_significance=1}. Variant chr19-49168301-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TRPM4	NM_017636.4	c.490C>T	p.Arg164Trp	missense_variant	5/25	ENST00000252826.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TRPM4	ENST00000252826.10	c.490C>T	p.Arg164Trp	missense_variant	5/25	1	NM_017636.4	P1

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD3 exomes AF: 0.0000119 AC: 3 AN: 251426 Hom.: 0 AF XY: 0.0000221 AC XY: 3 AN XY: 135908

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 SAS exome AF: 0.0000653

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.00000547 AC: 8 AN: 1461830 Hom.: 0 Cov.: 33 AF XY: 0.00000963 AC XY: 7 AN XY: 727222

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000464

Gnomad4 FIN exome AF: 0.0000187

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 30

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Progressive familial heart block type IB Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Oct 09, 2023	This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 164 of the TRPM4 protein (p.Arg164Trp). This variant is present in population databases (rs387907216, gnomAD 0.01%). This missense change has been observed in individual(s) with cardiac conduction disease (PMID: 20562447). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 35488). 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 tolerated. Experimental studies have shown that this missense change affects TRPM4 function (PMID: 20562447). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, no assertion criteria provided	literature only	OMIM	Aug 01, 2010	- -

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 03, 2021

The p.R164W variant (also known as c.490C>T), located in coding exon 5 of the TRPM4 gene, results from a C to T substitution at nucleotide position 490. The arginine at codon 164 is replaced by tryptophan, an amino acid with dissimilar properties. This alteration has been described to segregate with variable presentations of heart block in one family, and was suggested to affect channel activity in in vitro studies (Liu H et al. Circ Cardiovasc Genet, 2010 Aug;3:374-85). This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Uncertain	0.023	T
BayesDel_noAF	Uncertain	0.0
Cadd	Pathogenic	26
Dann	Pathogenic	1.0
DEOGEN2	Pathogenic	0.85	D;.
Eigen	Uncertain	0.24
Eigen_PC	Benign	0.097
FATHMM_MKL	Benign	0.49	N
LIST_S2	Uncertain	0.93	D;D
M_CAP	Benign	0.030	D
MetaRNN	Pathogenic	0.81	D;D
MetaSVM	Benign	-1.2	T
MutationAssessor	Uncertain	2.6	M;M
MutationTaster	Benign	0.78	D;D;D
PrimateAI	Uncertain	0.61	T
PROVEAN	Pathogenic	-5.9	D;D
REVEL	Benign	0.25
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0010	D;D
Polyphen		1.0	D;D
Vest4		0.87
MutPred		0.59		Loss of methylation at R164 (P = 0.0432);Loss of methylation at R164 (P = 0.0432);
MVP		0.88
MPC		0.44
ClinPred		0.93	D
GERP RS		3.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8
Varity_R		0.61
gMVP		0.77

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs387907216; hg19: chr19-49671558;