rs879254788

Positions:

• chr19-11111544-G-A
• chr19-11111544-G-C
• chr19-11111544-G-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_000527.5(LDLR):​c.1091G>A​(p.Cys364Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. C364R) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 31)
• Consequence: LDLR NM_000527.5 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 9.77

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 Pathogenic. Variant got 18 ACMG points.

• PM1: In a strand (size 6) in uniprot entity LDLR_HUMAN there are 12 pathogenic changes around while only 1 benign (92%) in NM_000527.5
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr19-11111544-G-T is described in Lovd as [Likely_pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.995
• PP5: Variant 19-11111544-G-A is Pathogenic according to our data. Variant chr19-11111544-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 369852.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LDLR	NM_000527.5	c.1091G>A	p.Cys364Tyr	missense_variant	8/18	ENST00000558518.6	NP_000518.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LDLR	ENST00000558518.6	c.1091G>A	p.Cys364Tyr	missense_variant	8/18	1	NM_000527.5	ENSP00000454071	P3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hypercholesterolemia, familial, 1 Pathogenic:2

Likely pathogenic, criteria provided, single submitter	clinical testing	Molecular Genetics Laboratory, Centre for Cardiovascular Surgery and Transplantation	Nov 05, 2016	Disrupt disulfide bridge between Cys364 and Cys377. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Robarts Research Institute, Western University	-	- -

Cardiovascular phenotype Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 12, 2024

The p.C364Y variant (also known as c.1091G>A), located in coding exon 8 of the LDLR gene, results from a G to A substitution at nucleotide position 1091. The cysteine at codon 364 is replaced by tyrosine, an amino acid with highly dissimilar properties. Pathogenic LDLR mutations that result in the substitution or generation of cysteine residues within the cysteine-rich LDLR class A repeats and EGF-like domains are common in familial hypercholesterolemia (FH) (Villéger L. Hum Mutat. 2002;20(2):81-7). Internal structural analysis indicates this variant eliminates a disulfide bond critical for the structural integrity of the EGF-like 2 domain (Ambry internal data). This alteration, which is also known as p.C343Y, has been reported in individuals with FH (Wang J et al. Arterioscler Thromb Vasc Biol, 2016 Dec;36:2439-2445; Tichý L et al. Physiol Res, 2017 Apr;66:S47-S54; Pek SLT et al. Atherosclerosis, 2018 Feb;269:106-116; Sánchez-Hernández RM et al. J Clin Lipidol, 2019 May;13:618-626). Another variant at the same codon, p.C364R (c.1090T>C), has been detected in conjunction with another alteration in the LDLR gene in an individual whose protein activity was 15-30% of normal (Hobbs HH et al. Hum Mutat. 1992;1(6):445-66), and subsequent studies have reported this alteration in several individuals diagnosed with FH (Bertolini S et al. Arterioscler Thromb Vasc Biol. 2000;20(9):E41-52). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

Familial hypercholesterolemia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 29, 2020

For these reasons, this variant has been classified as Pathogenic. This variant disrupts the p.Cys364 amino acid residue in LDLR. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 1301956, 23375686, 26723464, 21722902, 25461735, 16314194, 10978268, 15556094). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has been observed in individual(s) with familial hypercholesterolemia (PMID: 31153816, 29353225, 27765764, 28379029). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 369852). This variant is not present in population databases (ExAC no frequency). This sequence change replaces cysteine with tyrosine at codon 364 of the LDLR protein (p.Cys364Tyr). The cysteine residue is highly conserved and there is a large physicochemical difference between cysteine and tyrosine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.59	D
BayesDel_noAF	Pathogenic	0.60
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.98	D;.;.;.;.;.
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.93
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.94	D;D;D;D;D;D
M_CAP	Pathogenic	0.96	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D
MetaSVM	Pathogenic	0.97	D
MutationAssessor	Pathogenic	4.9	H;.;.;.;.;H
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.60	T
PROVEAN	Pathogenic	-10	D;D;D;D;D;D
REVEL	Pathogenic	0.99
Sift	Pathogenic	0.0	D;D;D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D;D
Polyphen		1.0	D;.;.;.;.;.
Vest4		0.97
MutPred		0.94		Loss of disorder (P = 0.0727);Loss of disorder (P = 0.0727);.;.;.;Loss of disorder (P = 0.0727);
MVP		1.0
MPC		1.1
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.99
gMVP		1.0

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: rs879254788; hg19: chr19-11222220;