rs751317621

Positions:

• chr19-11100281-C-A
• chr19-11100281-C-G
• chr19-11100281-C-T

Variant summary

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

The ENST00000558518.6(LDLR):​c.126C>A​(p.Tyr42Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,598 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: 6.8e-7 (0 hom.)
• Consequence: LDLR ENST00000558518.6 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 0.171

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 19-11100281-C-A is Pathogenic according to our data. Variant chr19-11100281-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 251028.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr19-11100281-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.126C>A	p.Tyr42Ter	stop_gained	2/18	ENST00000558518.6	NP_000518.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LDLR	ENST00000558518.6	c.126C>A	p.Tyr42Ter	stop_gained	2/18	1	NM_000527.5	ENSP00000454071	P3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461598 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727074

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: 0.0000116

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

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hypercholesterolemia, familial, 1 Pathogenic:3

Pathogenic, criteria provided, single submitter	research	Laboratory of Genetics and Molecular Cardiology, University of São Paulo	Mar 01, 2016	- -
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	-	- -

Homozygous familial hypercholesterolemia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Apr 02, 2019

The p.Tyr42X variant in LDLR has been reported in the heterozygous state in 3 individuals with familial hypercholesterolemia (FH) and in 1 individual with definite or probable FH who also had a loss of function variant in PCSK9 (Bertolini 2013, Jannes 2015, Pirillo 2017). This variant has also been reported in ClinVar (Variation ID: 251028) and was absent from large population studies. This nonsense variant leads to a premature termination codon at position 42, 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 the predicted impact to the protein, absence from the general population and presence in affected individuals. ACMG/AMP Criteria applied: PVS1, PM2, PS4_Supporting. -

Familial hypercholesterolemia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 29, 2021

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 251028). This premature translational stop signal has been observed in individual(s) with familial hypercholesterolemia (PMID: 23375686, 28965616). This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Tyr42*) 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). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Uncertain	0.090
CADD	Pathogenic	34
DANN	Uncertain	0.98
Eigen	Benign	-0.17
Eigen_PC	Benign	-0.47
FATHMM_MKL	Benign	0.35	N
MutationTaster	Benign	1.0	A;A;A;A;A;A;D
Vest4		0.56
GERP RS		-4.0

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: rs751317621; hg19: chr19-11210957;