rs199774121

Positions:

• chr19-11105335-C-A

Variant summary

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

The ENST00000558518.6(LDLR):​c.429C>A​(p.Cys143Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000616 in 1,461,586 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 Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000062 (0 hom.)
• Consequence: LDLR ENST00000558518.6 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:14
• Conservation: PhyloP100: 0.243

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 19-11105335-C-A is Pathogenic according to our data. Variant chr19-11105335-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 226325.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr19-11105335-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.429C>A	p.Cys143Ter	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.429C>A	p.Cys143Ter	stop_gained	4/18	1	NM_000527.5	ENSP00000454071	P3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251178 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135822

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000616 AC: 9 AN: 1461586 Hom.: 0 Cov.: 33 AF XY: 0.00000825 AC XY: 6 AN XY: 727118

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000809

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.0000247 AC: 3

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:14

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hypercholesterolemia, familial, 1 Pathogenic:9

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	- -
Pathogenic, no assertion criteria provided	research	Laboratorium voor Moleculaire Diagnostiek Experimentele Vasculaire Geneeskunde, Academisch Medisch Centrum	-	- -
Pathogenic, criteria provided, single submitter	research	Fundacion Hipercolesterolemia Familiar	Mar 01, 2016	- -
Pathogenic, no assertion criteria provided	clinical testing	Cardiovascular Genetics Laboratory, PathWest Laboratory Medicine WA - Fiona Stanley Hospital	Feb 18, 2016	- -
Pathogenic, criteria provided, single submitter	clinical testing	Department of Human Genetics, Laborarztpraxis Dres. Walther, Weindel und Kollegen	May 08, 2018	This nonsense mutation leads to a complete loss of the receptor function. In addition, the variant was observed in multiple studies in patients with FH. In our case the mutation was observed in a patient with TC up to 550 mg/dl at the age of 35. PMID: 9212177, 25487149 -
Pathogenic, no assertion criteria provided	clinical testing	Clinical Genomics Laboratory, Stanford Medicine	Dec 31, 2020	The p.Cys143* variant in the LDLR gene has been previously reported in at least 22 unrelated individuals with familial hypercholesterolemia (Descamps et al., 1997; Ekström et al., 1998; Lombardi et al., 1998; Jensen et al., 1999; Amsellem et al., 2002; van der Graaf et al., 2011; Natarajan et al., 2016), and one paper reported that it co-segregated with known or suspected FH in 71 relatives from 11 unrelated families (Descamps et al., 1997). This variant is also known as p.Cys122* in the literature. The p.Cys143* variant has been identified in 2/113,608 European (non-Finnish) chromosomes by the Genome Aggregation Database (http://gnomad.broadinstitute.org/). This variant leads to a premature stop codon in exon 4 of 18 coding exons, and is therefore predicted to undergo nonsensemediated decay resulting in a truncated or absent protein. Heterozygous loss of function is an established mechanism of disease for the LDLR gene. These data were assessed using the ACMG/AMP variant interpretation guidelines. In summary, there is sufficient evidence to classify the p.Cys143* variant as pathogenic for autosomal dominant familial hypercholesterolemia based on the information above. [ACMG evidence codes used: PVS1; PS4; PM2] -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics, University of Leipzig Medical Center	Mar 05, 2024	Criteria applied: PVS1,PS4,PM2_SUP -
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	- -

not provided Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Dec 03, 2020	This nonsense variant causes the premature termination of LDLR protein synthesis. It has been reported in individuals affected with familial hypercholesteremia in the published literature (PMID: 9767373 (1998), 9452078 (1998), 27831900 (2016), 21382890 (2011), 19318025 (2009)). Therefore, the variant is classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Institute for Clinical Genetics, University Hospital TU Dresden, University Hospital TU Dresden	Sep 08, 2022	PVS1, PS4, PP3 -
Pathogenic, criteria provided, single submitter	clinical testing	Clinical Genetics Laboratory, Skane University Hospital Lund	Nov 06, 2023	- -

Cardiovascular phenotype Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 01, 2019

The p.C143* pathogenic mutation (also known as c.429C>A), located in coding exon 4 of the LDLR gene, results from a C to A substitution at nucleotide position 429. This changes the amino acid from a cysteine to a stop codon within coding exon 4. This alteration has been reported in multiple subjects with familial hypercholesterolemia (FH) (Descamps O et al. Clin. Genet., 1997 May;51:303-8; Lombardi P et al. Hum. Mutat., 1998;Suppl 1:S172-4; Amsellem S et al. Hum. Genet., 2002 Dec;111:501-10; van der Graaf A et al. Circulation, 2011 Mar;123:1167-73). 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. -

Familial hypercholesterolemia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 17, 2023

This sequence change creates a premature translational stop signal (p.Cys143*) in the LDLR gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in LDLR are known to be pathogenic (PMID: 20809525, 28645073). This variant is present in population databases (rs199774121, gnomAD 0.003%). This premature translational stop signal has been observed in individuals with familial hypercholesterolemia (PMID: 9212177, 16542394, 21382890, 27831900). It has also been observed to segregate with disease in related individuals. This variant is also known as p.Cys122*. ClinVar contains an entry for this variant (Variation ID: 226325). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.50
CADD	Pathogenic	33
DANN	Uncertain	0.99
Eigen	Uncertain	0.22
Eigen_PC	Benign	-0.042
FATHMM_MKL	Uncertain	0.96	D
MutationTaster	Benign	1.0	A;A;A;A;D;D;D
Vest4		0.84
GERP RS		1.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.13		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: rs199774121; hg19: chr19-11216011;