NM_000527.5:c.826T>C

Variant names:

• chr19-11107400-T-C
• rs879254692
• NM_000527.5:c.826T>C

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2 PM1 PS4_Supporting PP3 PP4

This summary comes from the ClinGen Evidence Repository: The NM_000527.5(LDLR):c.826T>C (p.Cys276Arg) variant is classified as Likely Pathogenic for Familial Hypercholesterolemia by applying ACMG/AMP evidence codes PM1, PM2, PP3, PP4 and PS4_Supporting as defined by the ClinGen Familial Hypercholesterolemia Expert Panel LDLR-specific variant curation guidelines (specification version 1.2) on 28 October 2022. The supporting evidence is as follows: PM1: Variant meets PM2 and alters Cys276.PM2: This variant is absent from gnomAD v2.1.1.PP3: REVEL = 0.915.PS4_Supporting, PP4: Variant meets PM2 and is identified in at least 3 unrelated index cases who fulfill criteria for FH (3 cases from PMID 10978268 (Bertolini et al. 2000)). LINK:https://erepo.genome.network/evrepo/ui/classification/CA10585154/MONDO:0007750/013

• Frequency: Genomes: not found (cov: 32)
• Consequence: LDLR NM_000527.5 missense
• Clinical Significance: Likely pathogenic reviewed by expert panel P:6 U:1
• Conservation: PhyloP100: 6.13

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PS4: For more information check the summary or visit ClinGen Evidence Repository.
• PM1: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: 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.826T>C	p.Cys276Arg	missense_variant	Exon 6 of 18	ENST00000558518.6	NP_000518.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LDLR	ENST00000558518.6	c.826T>C	p.Cys276Arg	missense_variant	Exon 6 of 18	1	NM_000527.5	ENSP00000454071.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:6 Uncertain:1

Revision: reviewed by expert panel

Submissions by phenotype

Hypercholesterolemia, familial, 1 Pathogenic:4

Jul 10, 2024

Institute of Human Genetics, University of Leipzig Medical Center

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Criteria applied: PM5_STR,PS4_MOD,PM1,PM3,PM2_SUP,PP3 -

Dec 16, 2016

Centre de Génétique Moléculaire et Chromosomique, Unité de génétique de l'Obésité et des Dyslipidémies, APHP, GH Hôpitaux Universitaires Pitié-Salpêtrière / Charles-Foix

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

subjects mutated among 2600 FH index cases screened = 2 / FH-Ceva / Software predictions: Damaging -

Mar 25, 2016

LDLR-LOVD, British Heart Foundation

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: literature only

- -

Oct 28, 2022

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.826T>C (p.Cys276Arg) variant is classified as Likely Pathogenic for Familial Hypercholesterolemia by applying ACMG/AMP evidence codes PM1, PM2, PP3, PP4 and PS4_Supporting as defined by the ClinGen Familial Hypercholesterolemia Expert Panel LDLR-specific variant curation guidelines (specification version 1.2) on 28 October 2022. The supporting evidence is as follows: PM1: Variant meets PM2 and alters Cys276. PM2: This variant is absent from gnomAD v2.1.1. PP3: REVEL = 0.915. PS4_Supporting, PP4: Variant meets PM2 and is identified in at least 3 unrelated index cases who fulfill criteria for FH (3 cases from PMID 10978268 (Bertolini et al. 2000)). -

not provided Pathogenic:1

May 17, 2023

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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; Also known as p.C255R; This variant is associated with the following publications: (PMID: 30710474, 23375686, 10978268) -

Familial hypercholesterolemia Pathogenic:1

Dec 03, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces cysteine, which is neutral and slightly polar, with arginine, which is basic and polar, at codon 276 of the LDLR protein (p.Cys276Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with familial hypercholesterolemia (PMID: 10978268). This variant is also known as C255R. ClinVar contains an entry for this variant (Variation ID: 251479). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt LDLR protein function with a positive predictive value of 95%. This variant affects a cysteine residue located within an LDLRA or epidermal-growth-factor (EGF)-like domains of the LDLR protein. Cysteine residues in these domains have been shown to be involved in the formation of disulfide bridges, which are critical for protein structure and stability (PMID: 7548065, 7603991, 7979249). In addition, missense substitutions within the LDLRA and EGF-like domains affecting cysteine residues are overrepresented among patients with hypercholesterolemia (PMID: 18325082). This variant disrupts the p.Cys276 amino acid residue in LDLR. Other variant(s) that disrupt this residue have been observed in individuals with LDLR-related conditions (PMID: 10634824, 26361156), which suggests that this may be a clinically significant amino acid residue. For these reasons, this variant has been classified as Pathogenic. -

not specified Uncertain:1

Nov 10, 2017

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: The LDLR c.826T>C (p.Cys276Arg) variant involves the alteration of a conserved nucleotide that results in the alteration of a cysteine residue at the protein level that is highly conserved across species (Bertolini 2013). The variant is located in the ligand-binding domain of the LDL receptor (InterPro). 4/4 in silico tools predict a damaging outcome for this variant (SNPsandGO not captured due to low reliability index), however these predictions have not been evaluated for functional impact by in vivo/vitro studies. This variant is absent in 246246 control chromosomes (gnomAD). The variant has been reported in individuals presented with hypercholesterolemia in heterozygous form (Bertolini 2003), however without providing clear evidence for causality. One clinical diagnostic laboratoy and a databases classified this variant as likely pathogenic, without evidence for independent evaluation. Variants involving the same codon such as C276G, C276F, C276W, and C276Y have been reported in affected individuals suggesting the functional importance of this codon. Taken together, this variant is classified as VUS-possibly pathogenic, until additional evidence becomes available. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.57
CADD	Uncertain	25
DANN	Uncertain	0.98
DEOGEN2	Pathogenic	0.93	D;.;.;.;.;.
Eigen	Uncertain	0.59
Eigen_PC	Uncertain	0.43
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D;D;T;D;D;D
M_CAP	Pathogenic	0.93	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.3	H;.;.;.;.;H
PrimateAI	Uncertain	0.74	T
PROVEAN	Pathogenic	-9.9	D;D;D;D;D;D
REVEL	Pathogenic	0.92
Sift	Pathogenic	0.0	D;D;D;D;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D;D;D
Polyphen		0.99	D;.;.;.;.;.
Vest4		0.98
MutPred		0.83		Gain of ubiquitination at K281 (P = 0.0668);Gain of ubiquitination at K281 (P = 0.0668);.;.;.;Gain of ubiquitination at K281 (P = 0.0668);
MVP		1.0
MPC		1.1
ClinPred		1.0	D
GERP RS		5.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.98
gMVP		0.99

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

Other links and lift over

dbSNP: rs879254692; hg19: chr19-11218076;