19-11113314-A-T

Variant names:

• chr19-11113314-A-T
• rs879254838
• NM_000527.5:c.1223A>T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PP1_Moderate PM2 PP3 PP4 PS4_Moderate

This summary comes from the ClinGen Evidence Repository: The NM_000527.5(LDLR):c.1223A>T (p.Glu408Val) variant is classified as Likely pathogenic for Familial Hypercholesterolemia by applying evidence codes PP1_Moderate, PM2, PS4_Moderate, PP3 and PP4 as defined by the ClinGen Familial Hypercholesterolemia Expert Panel LDLR-specific variant curation guidelines (https://doi.org/10.1101/2021.03.17.21252755). The supporting evidence is as follows: PP1_moderate - variant segregates with FH phenotype in 5 informative meiosis (data from 3 families: F1 - 2 affected family members have the variant, F2 - 2 affected family members have the variant, F3 - 1 affected family member has the variant) from the Molecular Genetics Laboratory (Centre for Cardiovascular Surgery and Transplantation), so PP1_Moderate is met.PM2 - This variant was not identified in gnomAD (gnomAD v2.1.1), so PM2 is met.PS4_moderate - variant meets PM2 and was identified in 6 unrelated index cases, all fulfilling Simon-Broome criteria of definite FH, from the Molecular Genetics Laboratory (Centre for Cardiovascular Surgery and Transplantation), so PS4_Moderate is met.PP3 - REVEL = 0.908. It is above 0.75, so PP3 is met.PP4 - variant meets PM2 and was identified in 6 unrelated index cases (see details in PS4), so PP4 is met. LINK:https://erepo.genome.network/evrepo/ui/classification/CA10585364/MONDO:0007750/013

• Frequency: Genomes: not found (cov: 29)
• Consequence: LDLR NM_000527.5 missense
• Clinical Significance: Likely pathogenic reviewed by expert panel P:8
• Conservation: PhyloP100: 9.13

Genes affected

LDLR (HGNC:6547): (low density lipoprotein receptor) The low density lipoprotein receptor (LDLR) gene family consists of cell surface proteins involved in receptor-mediated endocytosis of specific ligands. The encoded protein is normally bound at the cell membrane, where it binds low density lipoprotein/cholesterol and is taken into the cell. Lysosomes release the cholesterol, which is made available for repression of microsomal enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase, the rate-limiting step in cholesterol synthesis. At the same time, a reciprocal stimulation of cholesterol ester synthesis takes place. Mutations in this gene cause the autosomal dominant disorder, familial hypercholesterolemia. Alternate splicing results in multiple transcript variants.[provided by RefSeq, May 2022]

MIR6886 (HGNC:50121): (microRNA 6886) microRNAs (miRNAs) are short (20-24 nt) non-coding RNAs that are involved in post-transcriptional regulation of gene expression in multicellular organisms by affecting both the stability and translation of mRNAs. miRNAs are transcribed by RNA polymerase II as part of capped and polyadenylated primary transcripts (pri-miRNAs) that can be either protein-coding or non-coding. The primary transcript is cleaved by the Drosha ribonuclease III enzyme to produce an approximately 70-nt stem-loop precursor miRNA (pre-miRNA), which is further cleaved by the cytoplasmic Dicer ribonuclease to generate the mature miRNA and antisense miRNA star (miRNA*) products. The mature miRNA is incorporated into a RNA-induced silencing complex (RISC), which recognizes target mRNAs through imperfect base pairing with the miRNA and most commonly results in translational inhibition or destabilization of the target mRNA. The RefSeq represents the predicted microRNA stem-loop. [provided by RefSeq, Sep 2009]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PS4: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PP1: For more information check the summary or visit ClinGen Evidence Repository.
• PP3: For more information check the summary or visit ClinGen Evidence Repository.
• PP4: For more information check the summary or visit ClinGen Evidence Repository.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LDLR	NM_000527.5	c.1223A>T	p.Glu408Val	missense_variant	Exon 9 of 18	ENST00000558518.6	NP_000518.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LDLR	ENST00000558518.6	c.1223A>T	p.Glu408Val	missense_variant	Exon 9 of 18	1	NM_000527.5	ENSP00000454071.1

Frequencies

GnomAD3 genomes Cov.: 29

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 29

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:8

Revision: reviewed by expert panel

Submissions by phenotype

Hypercholesterolemia, familial, 1 Pathogenic:5

Dec 16, 2021

ClinGen Familial Hypercholesterolemia Variant Curation Expert Panel

Significance: Likely pathogenic

Review Status: reviewed by expert panel

Collection Method: curation

The NM_000527.5(LDLR):c.1223A>T (p.Glu408Val) variant is classified as Likely pathogenic for Familial Hypercholesterolemia by applying evidence codes PP1_Moderate, PM2, PS4_Moderate, PP3 and PP4 as defined by the ClinGen Familial Hypercholesterolemia Expert Panel LDLR-specific variant curation guidelines (https://doi.org/10.1101/2021.03.17.21252755). The supporting evidence is as follows: PP1_moderate - variant segregates with FH phenotype in 5 informative meiosis (data from 3 families: F1 - 2 affected family members have the variant, F2 - 2 affected family members have the variant, F3 - 1 affected family member has the variant) from the Molecular Genetics Laboratory (Centre for Cardiovascular Surgery and Transplantation), so PP1_Moderate is met. PM2 - This variant was not identified in gnomAD (gnomAD v2.1.1), so PM2 is met. PS4_moderate - variant meets PM2 and was identified in 6 unrelated index cases, all fulfilling Simon-Broome criteria of definite FH, from the Molecular Genetics Laboratory (Centre for Cardiovascular Surgery and Transplantation), so PS4_Moderate is met. PP3 - REVEL = 0.908. It is above 0.75, so PP3 is met. PP4 - variant meets PM2 and was identified in 6 unrelated index cases (see details in PS4), so PP4 is met. -

Nov 05, 2016

Molecular Genetics Laboratory, Centre for Cardiovascular Surgery and Transplantation

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mar 25, 2016

LDLR-LOVD, British Heart Foundation

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: literature only

- -

Jan 26, 2019

Brunham Lab, Centre for Heart and Lung Innovation, University of British Columbia

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: research

- -

Nov 21, 2022

Revvity Omics, Revvity

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Pathogenic:1

Jan 30, 2023

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Also known as p.(E387V); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Published functional studies suggest a damaging effect as CHO cells transfected with this variant showed reduced plasma membrane expression and reduced LDL particle uptake (Duskova et al., 2020); This variant is associated with the following publications: (PMID: 21310417, 22698793, 32695144, 33740630) -

Cardiovascular phenotype Pathogenic:1

Aug 12, 2024

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1223A>T (p.E408V) alteration is located in exon 9 (coding exon 9) of the LDLR gene. This alteration results from a A to T substitution at nucleotide position 1223, causing the glutamic acid (E) at amino acid position 408 to be replaced by a valine (V). This variant was not reported in population-based cohorts in the Genome Aggregation Database (gnomAD). This alteration has been reported in association with familial hypercholesterolemia (FH) (Dušková, 2011; Tichý, 2012). Another variant at the same codon, p.E408K (c.1222G>A), has been described in association with FH (Hobbs, 1992). This amino acid position is well conserved in available vertebrate species. This alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, this alteration is classified as likely pathogenic. -

Familial hypercholesterolemia Pathogenic:1

Oct 04, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glutamic acid, which is acidic and polar, with valine, which is neutral and non-polar, at codon 408 of the LDLR protein (p.Glu408Val). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with familial hypercholesterolemia (PMID: 22698793). ClinVar contains an entry for this variant (Variation ID: 251740). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt LDLR protein function. This variant disrupts the p.Glu408 amino acid residue in LDLR. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 1301956, 14974088, 17347910, 19843101, 20236128). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.73
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.41
CADD	Pathogenic	27
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.88	D;.;.;.;.;.
Eigen	Uncertain	0.53
Eigen_PC	Uncertain	0.46
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D;D;D;D;D;D
M_CAP	Pathogenic	0.91	D
MetaRNN	Pathogenic	0.95	D;D;D;D;D;D
MetaSVM	Pathogenic	0.88	D
MutationAssessor	Benign	1.9	L;.;.;.;.;L
PrimateAI	Uncertain	0.56	T
PROVEAN	Pathogenic	-6.4	D;D;D;D;D;D
REVEL	Pathogenic	0.91
Sift	Uncertain	0.0010	D;D;D;D;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D;D;D
Polyphen		0.67	P;.;.;.;.;.
Vest4		0.68
MutPred		0.70		Gain of MoRF binding (P = 0.0289);Gain of MoRF binding (P = 0.0289);.;.;.;Gain of MoRF binding (P = 0.0289);
MVP		1.0
MPC		0.77
ClinPred		1.0	D
GERP RS		4.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.82
gMVP		0.98

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.15		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: rs879254838; hg19: chr19-11223990;