rs193922567

Positions:

• chr19-11113451-T-A
• chr19-11113451-T-C

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1_Moderate PM2 PP5_Very_Strong

The NM_000527.5(LDLR):​c.1358+2T>A variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,612 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 29)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: LDLR NM_000527.5 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:18
• Conservation: PhyloP100: 7.84

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]

MIR6886 (HGNC:50121): (microRNA 6886) microRNAs (miRNAs) are short (20-24 nt) non-coding RNAs that are involved in post-transcriptional regulation of gene expression in multicellular organisms by affecting both the stability and translation of mRNAs. miRNAs are transcribed by RNA polymerase II as part of capped and polyadenylated primary transcripts (pri-miRNAs) that can be either protein-coding or non-coding. The primary transcript is cleaved by the Drosha ribonuclease III enzyme to produce an approximately 70-nt stem-loop precursor miRNA (pre-miRNA), which is further cleaved by the cytoplasmic Dicer ribonuclease to generate the mature miRNA and antisense miRNA star (miRNA*) products. The mature miRNA is incorporated into a RNA-induced silencing complex (RISC), which recognizes target mRNAs through imperfect base pairing with the miRNA and most commonly results in translational inhibition or destabilization of the target mRNA. The RefSeq represents the predicted microRNA stem-loop. [provided by RefSeq, Sep 2009]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.06620209 fraction of the gene. Cryptic splice site detected, with MaxEntScore 9.2, offset of 36, new splice context is: cagGTgaga. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 19-11113451-T-A is Pathogenic according to our data. Variant chr19-11113451-T-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 36455.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr19-11113451-T-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.1358+2T>A		splice_donor_variant		ENST00000558518.6	NP_000518.1
MIR6886	NR_106946.1			upstream_gene_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LDLR	ENST00000558518.6	c.1358+2T>A		splice_donor_variant		1	NM_000527.5	ENSP00000454071	P3
MIR6886	ENST00000619864.1			upstream_gene_variant

Frequencies

GnomAD3 genomes Cov.: 29

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461612 Hom.: 0 Cov.: 33 AF XY: 0.00000550 AC XY: 4 AN XY: 727116

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: 0.00000450

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 29

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:18

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hypercholesterolemia, familial, 1 Pathogenic:6

Pathogenic, no assertion criteria provided	clinical testing	Cardiovascular Genetics Laboratory, PathWest Laboratory Medicine WA - Fiona Stanley Hospital	Jun 05, 2008	- -
Pathogenic, no assertion criteria provided	research	Laboratorium voor Moleculaire Diagnostiek Experimentele Vasculaire Geneeskunde, Academisch Medisch Centrum	-	- -
Likely pathogenic, criteria provided, single submitter	literature only	LDLR-LOVD, British Heart Foundation	Mar 25, 2016	- -
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 -
Pathogenic, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Jun 08, 2023	This variant causes a T to A nucleotide substitution at the +2 position of intron 9 of the LDLR gene. Splice site prediction tools predict that this variant may have a significant impact on RNA splicing. Although functional RNA studies have not been reported for this variant, it is expected to cause aberrant splicing and result in an absent or disrupted protein product.. This variant has been reported in over 10 individuals affected with familial hypercholesterolemia (PMID: 11196104, 11462246, 21310417, 22698793, 22883975, 28008010). This variant has been identified in 1/245944 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Loss of LDLR function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Molecular Genetics Laboratory, Centre for Cardiovascular Surgery and Transplantation	Nov 05, 2016	- -

Familial hypercholesterolemia Pathogenic:5

Pathogenic, criteria provided, single submitter	clinical testing	Human Genome Sequencing Center Clinical Lab, Baylor College of Medicine	Jul 08, 2019	The c.1358+2T>A variant in the LDLR gene is predicted to disrupt a canonical splice site and thus alter the wild type mRNA splicing. This variant has been reported in multiple individuals affected with familial hypercholesterolemia (PMID 11196104, 11462246, 15199436, 16250003, 21310417) and is absent from general population databases. Therefore, this c.1358+2T>A variant in the LDLR gene is classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jan 30, 2023	Variant summary: LDLR c.1358+2T>A is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Several computational tools predict a significant impact on normal splicing: Five predict the variant abolishes a 5' splicing donor site. However, these predictions have yet to be confirmed by functional studies. The variant was absent in 251086 control chromosomes. c.1358+2T>A has been reported in the literature in multiple individuals affected with Familial Hypercholesterolemia (Weiss_2000, Nauck_2001, Tichy_2012, Leren_2021, etc.). These data indicate that the variant is very likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. 12 clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. Laboratories classified the variant as pathogenic (n=10) or likely pathogenic (n=2). Based on the evidence outlined above, the variant was classified as pathogenic. -
Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 15, 2023	This variant causes a T to A nucleotide substitution at the +2 position of intron 9 of the LDLR gene. Splice site prediction tools predict that this variant may have a significant impact on RNA splicing. Although functional RNA studies have not been reported for this variant, it is expected to cause aberrant splicing and result in an absent or disrupted protein product.. This variant has been reported in over 10 individuals affected with familial hypercholesterolemia (PMID: 11196104, 11462246, 21310417, 22698793, 22883975, 28008010). This variant has been identified in 1/245944 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Loss of LDLR function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Dec 06, 2023	This sequence change affects a donor splice site in intron 9 of the LDLR gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in LDLR are known to be pathogenic (PMID: 20809525, 28645073). This variant is present in population databases (rs193922567, gnomAD 0.0009%). Disruption of this splice site has been observed in individuals with LDLR-related conditions (PMID: 11196104, 11462246, 12124988, 21310417). ClinVar contains an entry for this variant (Variation ID: 36455). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:4

Likely pathogenic, criteria provided, single submitter	clinical testing	Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen	Oct 23, 2020	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Aug 08, 2023	Identified in several unrelated individuals from different ethnic backgrounds with FH in published literature (Weiss et al., 2000; Nauck et al., 2001; Fouchier et al., 2005; Duskova et al., 2011; Tichy et al., 2012; Hooper et al., 2012) and in several patients with FH referred for genetic testing at GeneDx; Not observed at significant frequency in large population cohorts (gnomAD); Canonical splice site variant predicted to result in a null allele in a gene for which loss of function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 25525159, 11196104, 21310417, 11462246, 12124988, 16250003, 15199436, 22883975, 22698793, 34040191, 33740630, 32770674, 34037665, 35913489) -
Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Aug 16, 2022	The LDLR c.1358+2T>A variant disrupts a canonical splice-donor site and interferes with normal LDLR mRNA splicing. This variant has been reported in the published literature in multiple individuals and families with familial hypercholesterolemia (PMIDs: 11196104 (2000), 11462246 (2001), 22698793 (2012), 22883975 (2012), 32770674 (2020), 33740630 (2021), 34037665 (2021)). This variant has not been reported in large, multi-ethnic general populations (Genome Aggregation Database, http://gnomad.broadinstitute.org). Based on the available information, this variant is classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Mar 06, 2023	The LDLR c.1358+2T>A variant (rs193922567) is reported in the literature in multiple individuals affected with familial hypercholesterolemia (Leren 2021, Nauck 2001, Rieck 2020, Tichy 2012, Weiss 2000). This variant is also reported in ClinVar (Variation ID: 36455) and is absent from the Genome Aggregation Database, indicating it is not a common polymorphism. This variant disrupts the canonical splice donor site of intron 9, which is likely to negatively impact gene function. Based on available information, this variant is considered to be pathogenic. References: Leren TP et al. Molecular genetic testing for autosomal dominant hypercholesterolemia in 29,449 Norwegian index patients and 14,230 relatives during the years 1993-2020. Atherosclerosis. 2021 Apr;322:61-66. PMID: 33740630. Nauck MS et al. Identification of recurrent and novel mutations in the LDL receptor gene in German patients with familial hypercholesterolemia. Hum Mutat. 2001 Aug;18(2):165-6. doi: 10.1002/humu.1171. PMID: 11462246 Rieck L et al. Mutation spectrum and polygenic score in German patients with familial hypercholesterolemia. Clin Genet. 2020 Nov;98(5):457-467. PMID: 32770674. Tichy L et al. The molecular basis of familial hypercholesterolemia in the Czech Republic: spectrum of LDLR mutations and genotype-phenotype correlations. Atherosclerosis. 2012 Aug;223(2):401-8. PMID: 22698793. Weiss N et al. Mutations in the low-density-lipoprotein receptor gene in German patients with familial hypercholesterolaemia. J Inherit Metab Dis. 2000 Dec;23(8):778-90. PMID: 11196104. -

Homozygous familial hypercholesterolemia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Mar 29, 2019

The c.1358+2T>A variant in LDLR has been reported in 2 individuals with familial hypercholesterolemia and segregated with disease in both families (Weiss 2000, Nauck 2001). This variant has also been identified in 1/66288 European chromosomes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org; dbSNP rs193922567). However, this frequency is low enough to be consistent with the frequency of familial hypercholesterolemia in the general population. This variant occurs in the invariant region (+/- 1,2) of the splice consensus sequence and is predicted to cause altered splicing leading to an abnormal or absent protein. Heterozygous loss of LDLR function is an established disease mechanism in familial hypercholesterolemia. In summary, this variant meets our criteria to be classified as pathogenic for familial hypercholesterolemia in an autosomal dominant manner based upon the predicted impact to the protein. -

See cases Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Institute of Human Genetics, University Hospital Muenster

Jan 26, 2022

ACMG categories: PVS1,PM2,PP5 -

Cardiovascular phenotype Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 09, 2022

The c.1358+2T>A intronic pathogenic mutation results from a T to A substitution two nucleotides after coding exon 9 in the LDLR gene. The mutation was detected in a patient diagnosed with familial hypercholesterolemia (FH) and in individuals from FH cohorts (Weiss N et al., J. Inherit. Metab. Dis. 2000 Dec; 23(8):778-90; Fouchier SW et al. Hum Mutat. 2005 Dec;26(6):550-6; Tichý L et al. Atherosclerosis. 2012 Aug;223(2):401-8). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). In silico splice site analysis predicts that this alteration will weaken the native splice donor site and will result in the creation or strengthening of a novel splice donor site. In addition to the clinical data presented in the literature, alterations that disrupt the canonical splice site are expected to cause aberrant splicing, resulting in an abnormal protein or a transcript that is subject to nonsense-mediated mRNA decay. As such, this alteration is classified 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	0.13
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Pathogenic	0.98
Eigen_PC	Pathogenic	0.79
FATHMM_MKL	Pathogenic	0.99	D
MutationTaster	Benign	1.0	A;A;A;A;A;A;A
GERP RS		4.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.92
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.65		Position offset: 34
DS_DL_spliceai		1.0		Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs193922567; hg19: chr19-11224127;