rs138657343

Positions:

chr18-31591916-G-A

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_StrongBP6BS2_Supporting

The ENST00000237014.8(TTR):c.14G>A(p.Arg5His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000141 in 1,614,140 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign 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. R5C) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00018 ( 1 hom., cov: 33)

Exomes 𝑓: 0.00014 ( 0 hom. )

Consequence

TTR
ENST00000237014.8 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:9B:9O:1

Conservation

PhyloP100: -0.437

Variant links:

Genes affected

TTR (HGNC:12405): (transthyretin) This gene encodes one of the three prealbumins, which include alpha-1-antitrypsin, transthyretin and orosomucoid. The encoded protein, transthyretin, is a homo-tetrameric carrier protein, which transports thyroid hormones in the plasma and cerebrospinal fluid. It is also involved in the transport of retinol (vitamin A) in the plasma by associating with retinol-binding protein. The protein may also be involved in other intracellular processes including proteolysis, nerve regeneration, autophagy and glucose homeostasis. Mutations in this gene are associated with amyloid deposition, predominantly affecting peripheral nerves or the heart, while a small percentage of the gene mutations are non-amyloidogenic. The mutations are implicated in the etiology of several diseases, including amyloidotic polyneuropathy, euthyroid hyperthyroxinaemia, amyloidotic vitreous opacities, cardiomyopathy, oculoleptomeningeal amyloidosis, meningocerebrovascular amyloidosis and carpal tunnel syndrome. [provided by RefSeq, Aug 2017]

TTR links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.03921768).

BP6

Variant 18-31591916-G-A is Benign according to our data. Variant chr18-31591916-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 181697.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=8, Likely_benign=4, not_provided=1}. Variant chr18-31591916-G-A is described in Lovd as [Likely_benign].

BS2

High AC in GnomAd4 at 27 AD gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TTR	NM_000371.4 linkuse as main transcript	c.14G>A	p.Arg5His	missense_variant	1/4	ENST00000237014.8	NP_000362.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TTR	ENST00000237014.8 linkuse as main transcript	c.14G>A	p.Arg5His	missense_variant	1/4	1	NM_000371.4	ENSP00000237014	P1

Frequencies

GnomAD3 genomes

AF:

0.000177

AC:

AN:

152160

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.000660

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000250

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000111

AC:

AN:

251406

Hom.:

AF XY:

0.000103

AC XY:

AN XY:

135866

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.0000578

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.000277

Gnomad NFE exome

AF:

0.000150

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000137

AC:

200

AN:

1461862

Hom.:

Cov.:

AF XY:

0.000128

AC XY:

AN XY:

727226

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000894

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.0000927

Gnomad4 FIN exome

AF:

0.000356

Gnomad4 NFE exome

AF:

0.000143

Gnomad4 OTH exome

AF:

0.000149

GnomAD4 genome

AF:

0.000177

AC:

AN:

152278

Hom.:

Cov.:

AF XY:

0.000215

AC XY:

AN XY:

74462

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.000131

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.000660

Gnomad4 NFE

AF:

0.000250

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000165

Hom.:

Bravo

AF:

0.0000945

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000349

AC:

ExAC

AF:

0.000107

AC:

Asia WGS

AF:

0.000289

AC:

AN:

3478

EpiCase

AF:

0.000109

EpiControl

AF:

0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:9Benign:9Other:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:4Benign:6

Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Mar 01, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Aug 21, 2023	Reported in an individual with HCM who also harbored a variant in the MYBPC3 gene in published literature (Viswanathan et al., 2017); however, no segregation studies were described; In silico analysis supports that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 27249223, 31659433, 29121657, 32674397) -
Uncertain significance, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Nov 14, 2023	The TTR c.14G>A; p.Arg5His variant (rs138657343) is reported in the literature in an individual affected with hereditary transthyretin amyloidosis (Auer-Grumbach 2020) as well as in an individual with hypertrophic cardiomyopathy (Viswanathan 2017). This variant is also reported in ClinVar (Variation ID: 181697). It is found in the general population with an overall allele frequency of 0.013% (36/282806 alleles, including 1 homozygote) in the Genome Aggregation Database (v2.1.1). Computational analyses are uncertain whether this variant is neutral or deleterious (REVEL: 0.268). However, given the lack of clinical and functional data, the significance of the p.Arg5His variant is uncertain at this time. References: Auer-Grumbach M et al. Hereditary ATTR Amyloidosis in Austria: Prevalence and Epidemiological Hot Spots. J Clin Med. 2020 Jul 14;9(7):2234. PMID: 32674397. Viswanathan SK et al. Hypertrophic cardiomyopathy clinical phenotype is independent of gene mutation and mutation dosage. PLoS One. 2017 Nov 9;12(11):e0187948. PMID: 29121657. -
Likely benign, no assertion criteria provided	clinical testing	Clinical Genetics, Academic Medical Center	-	- -
Likely benign, no assertion criteria provided	clinical testing	Genome Diagnostics Laboratory, University Medical Center Utrecht	-	- -
Likely benign, no assertion criteria provided	clinical testing	Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+	-	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Mayo Clinic Laboratories, Mayo Clinic	Apr 26, 2023	- -
Likely benign, no assertion criteria provided	clinical testing	Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen	-	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Oct 09, 2019	- -
Likely benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -

Amyloidosis, hereditary systemic 1

Uncertain:3Other:1

Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Apr 27, 2017	This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -
Uncertain significance, no assertion criteria provided	clinical testing	Molecular Genetics Laboratory, BC Children's and BC Women's Hospitals	Aug 29, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 27, 2024	This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 5 of the TTR protein (p.Arg5His). This variant is present in population databases (rs138657343, gnomAD 0.03%). This missense change has been observed in individual(s) with clinical features of TTR-related conditions (PMID: 29121657, 32674397). ClinVar contains an entry for this variant (Variation ID: 181697). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The histidine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
not provided, no classification provided	phenotyping only	GenomeConnect, ClinGen	-	Variant classified as Uncertain significance and reported on 11-03-2021 by Lab or GTR ID 500031. GenomeConnect assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. GenomeConnect staff make no attempt to reinterpret the clinical significance of the variant. -

Cardiomyopathy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Mar 21, 2023

- -

TTR-related disorder

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Jun 01, 2023

The TTR c.14G>A variant is predicted to result in the amino acid substitution p.Arg5His. This variant was reported in an individual with Cardiomyopathy, hypertrophic (Table S3 Viswanathan et al. 2017. PubMed ID: 29121657) and in an individual with hereditary amyloidosis (Auer-Grumbach et al. 2020. PubMed ID: 32674397). This variant is reported in 0.032% of alleles in individuals of European (Finnish) descent in gnomAD (http://gnomad.broadinstitute.org/variant/18-29171879-G-A). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Charcot-Marie-Tooth disease

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Molecular Genetics Laboratory, London Health Sciences Centre

- -

not specified

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Aug 23, 2017

p.Arg5His in exon 1 of TTR: This variant is not expected to have clinical signif icance due to a lack of conservation across species, including mammals. Of note, >15 mammals, including chimpanzee, have a histidine (His) at this position. Thi s variant has been identified in 21/126636 European chromosomes, including 1 hom ozygote, by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitut e.org; dbSNP rs138657343). -

Cardiovascular phenotype

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 19, 2023

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.12

BayesDel_addAF

Benign

-0.23

BayesDel_noAF

Benign

-0.26

CADD

Benign

2.9

DANN

Benign

0.87

DEOGEN2

Benign

0.20

T;T;T;.

Eigen

Benign

-1.5

Eigen_PC

Benign

-1.5

FATHMM_MKL

Benign

0.051

LIST_S2

Benign

0.61

.;T;T;T

M_CAP

Benign

0.022

MetaRNN

Benign

0.039

T;T;T;T

MetaSVM

Uncertain

-0.23

MutationAssessor

Benign

0.48

N;N;.;.

MutationTaster

Benign

1.0

PrimateAI

Benign

0.20

PROVEAN

Benign

-0.55

.;N;.;.

REVEL

Benign

0.27

Sift

Benign

0.19

.;T;.;.

Sift4G

Benign

0.18

.;T;T;T

Polyphen

0.0020

B;B;.;.

Vest4

0.024, 0.086, 0.074

MVP

0.82

MPC

0.58

ClinPred

0.017

GERP RS

-5.1

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.031

gMVP

0.64

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over