rs879254548

Positions:

• chr19-11105406-G-A
• chr19-11105406-G-C

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.500G>A​(p.Cys167Tyr) 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. C167R) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: LDLR NM_000527.5 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 9.87

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 disulfide_bond (size 17) in uniprot entity LDLR_HUMAN there are 50 pathogenic changes around while only 1 benign (98%) 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 chr19-11105405-T-C is described in Lovd as [Likely_pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.997
• PP5: Variant 19-11105406-G-A is Pathogenic according to our data. Variant chr19-11105406-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 251256.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr19-11105406-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LDLR	NM_000527.5	c.500G>A	p.Cys167Tyr	missense_variant	4/18	ENST00000558518.6	NP_000518.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LDLR	ENST00000558518.6	c.500G>A	p.Cys167Tyr	missense_variant	4/18	1	NM_000527.5	ENSP00000454071	P3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hypercholesterolemia, familial, 1 Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Neuberg Centre For Genomic Medicine, NCGM	-	The missense variant c.500G>A (p.Cys167Tyr) in LDLR gene has been observed in several individuals affected with LDLR-related conditions (Miyake Y et.al.,2009). 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(Bieri S et.al.,1995). In addition, missense substitutions within the LDLRA and EGF-like domains affecting cysteine residues are overrepresented among patients with hypercholesterolemia (Leigh SE et.al.,2008). This variant has been reported to the ClinVar database as Likely Pathogenic. The p.Cys167Tyr variant is novel (not in any individuals) in gnomAD Exomes and 1000 Genomes. The amino acid Cys at position 167 is changed to a Tyr changing protein sequence and it might alter its composition and physico-chemical properties. For these reasons, this variant has been classified as Pathogenic. -
Likely pathogenic, criteria provided, single submitter	literature only	LDLR-LOVD, British Heart Foundation	Mar 25, 2016	- -

Familial hypercholesterolemia Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 12, 2018

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 is not present in population databases (ExAC no frequency). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. 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 several individuals affected with LDLR-related conditions (PMID: 11196104, 18718593). This variant is also known in the literature as Cys146Tyr. ClinVar contains an entry for this variant (Variation ID: 251256). This sequence change replaces cysteine with tyrosine at codon 167 of the LDLR protein (p.Cys167Tyr). 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	0.58	D
BayesDel_noAF	Pathogenic	0.60
CADD	Uncertain	26
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.98	D;.;.;.
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.95	D;D;D;D
M_CAP	Pathogenic	0.93	D
MetaRNN	Pathogenic	1.0	D;D;D;D
MetaSVM	Pathogenic	0.92	D
MutationAssessor	Pathogenic	4.7	H;.;.;H
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.71	T
PROVEAN	Pathogenic	-10	D;D;D;D
REVEL	Pathogenic	0.93
Sift	Uncertain	0.0010	D;D;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D
Polyphen		1.0	D;.;.;.
Vest4		0.99
MutPred		0.93		Loss of stability (P = 0.0201);Loss of stability (P = 0.0201);.;Loss of stability (P = 0.0201);
MVP		1.0
MPC		1.1
ClinPred		1.0	D
GERP RS		5.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.99
gMVP		1.0

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs879254548; hg19: chr19-11216082;