rs769318035

Positions:

• chr19-11105425-C-A
• chr19-11105425-C-G
• chr19-11105425-C-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000527.5(LDLR):​c.519C>A​(p.Cys173*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,740 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: LDLR NM_000527.5 stop_gained
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:7
• Conservation: PhyloP100: -0.169

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.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 19-11105425-C-A is Pathogenic according to our data. Variant chr19-11105425-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 251276.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr19-11105425-C-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LDLR	NM_000527.5	c.519C>A	p.Cys173*	stop_gained	4/18	ENST00000558518.6	NP_000518.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LDLR	ENST00000558518.6	c.519C>A	p.Cys173*	stop_gained	4/18	1	NM_000527.5	ENSP00000454071.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461740 Hom.: 0 Cov.: 33 AF XY: 0.00000275 AC XY: 2 AN XY: 727178

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hypercholesterolemia, familial, 1 Pathogenic:5

Pathogenic, criteria provided, single submitter	clinical testing	U4M - Lille University & CHRU Lille, Université de Lille - CHRU de Lille	Mar 30, 2017	- -
Pathogenic, criteria provided, single submitter	literature only	LDLR-LOVD, British Heart Foundation	Mar 25, 2016	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Centre de Génétique Moléculaire et Chromosomique, Unité de génétique de l'Obésité et des Dyslipidémies, APHP, GH Hôpitaux Universitaires Pitié-Salpêtrière / Charles-Foix	Dec 16, 2016	subject mutated among 2600 FH index cases screened = 1, family mermbers = 2/previously described in association with FH -
Pathogenic, criteria provided, single submitter	research	Fundacion Hipercolesterolemia Familiar	Mar 01, 2016	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Robarts Research Institute, Western University	-	- -

Homozygous familial hypercholesterolemia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Apr 10, 2019

The p.Cys173X variant (also reported as p.Cys152X in the literature) in LDLR has been reported in the heterozygous state in at least 3 individuals with familial hypercholesterolemia (FH; Vallve 1998, Graham 1999, Wang 2001, ClinVar accession IDs: SCV000484693.1, SCV000503174.1, SCV000583690.1) and was absent from large population studies. This nonsense variant leads to a premature termination codon at position 173, which is predicted to lead to a truncated or absent protein. Loss of function of the LDLR gene is an established disease mechanism in autosomal dominant FH. In summary, this variant meets criteria to be classified as pathogenic for autosomal dominant FH based upon predicted impact to the protein, absence from the general population and case observations. ACMG/AMP Criteria applied: PVS1, PM2, PS4_Supporting. -

Cardiovascular phenotype Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 14, 2024

The p.C173* pathogenic mutation (also known as c.519C>A), located in coding exon 4 of the LDLR gene, results from a C to A substitution at nucleotide position 519. This changes the amino acid from a cysteine to a stop codon within coding exon 4. This alteration, also reported as p.C152X, has been reported in familial hypercholesterolemia (FH) cohorts (Graham CA et al. Atherosclerosis, 1999 Dec;147:309-16; Wang J et al. Hum Mutat, 2001 Oct;18:359). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Uncertain	0.060
CADD	Pathogenic	28
DANN	Uncertain	0.98
Eigen	Benign	-0.35
Eigen_PC	Benign	-0.73
FATHMM_MKL	Uncertain	0.86	D
Vest4		0.82
GERP RS		-3.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8

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: rs769318035; hg19: chr19-11216101;