rs775924858

chr19-11113450-G-Achr19-11113450-G-Cchr19-11113450-G-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PVS1_Moderate PM2 PP3_Strong PP5_Very_Strong

The NM_000527.5(LDLR):c.1358+1G>A variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,652 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: 6.8e-7 (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:9
• Conservation: PhyloP100: 9.88

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 16 ACMG points.

• PVS1: Splicing variant, 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
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 19-11113450-G-A is Pathogenic according to our data. Variant chr19-11113450-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 251802.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr19-11113450-G-A is described in Lovd as [Pathogenic]. Variant chr19-11113450-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LDLR	NM_000527.5	c.1358+1G>A		splice_donor_variant		ENST00000558518.6
MIR6886	NR_106946.1			upstream_gene_variant

Ensembl

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

Frequencies

GnomAD3 genomes Cov.: 29

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461652 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727128

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.: 29

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:9

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hypercholesterolemia, familial, 1 Pathogenic:6

Pathogenic, no assertion criteria provided	research	Laboratorium voor Moleculaire Diagnostiek Experimentele Vasculaire Geneeskunde, Academisch Medisch Centrum	-	- -
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	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	research	Fundacion Hipercolesterolemia Familiar	Mar 01, 2016	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Robarts Research Institute, Western University	-	- -
Likely pathogenic, criteria provided, single submitter	literature only	LDLR-LOVD, British Heart Foundation	Mar 25, 2016	- -

Homozygous familial hypercholesterolemia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Apr 22, 2019

The c.1358+1G>A variant in LDLR has been reported in at least 10 individuals with familial hypercholesterolemia (FH) and segregated with disease in 1 affected relative from 1 family (Top 1993, Mozas 2004, Zakharova 2005, ClinVar submission accessions: SCV000484786.1, SCV000503339.1, SCV000583824.1). It was absent from large population studies. This variant occurs within the canonical splice site (+/- 1,2) and is predicted to cause altered splicing leading to an abnormal 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. ACMG/AMP Criteria applied: PVS1, PM2, PS4_Moderate. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Quest Diagnostics Nichols Institute San Juan Capistrano

Aug 02, 2021

This variant is located in a canonical splice-donor site and interferes with normal LDLR mRNA splicing. The variant has been reported in individuals affected with Familial Hypercholesteremia (FH) in the published literature (PMID: 24632281 (2014), 22390909 (2012), 19208450 (2009), 16627557 (2006), 15701167 (2005), 15241806 (2004)). Therefore, the variant is classified as pathogenic. -

Familial hypercholesterolemia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

May 19, 2023

For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 251802). This variant is also known as IVS9+1G>A. Disruption of this splice site has been observed in individuals with familial hypercholesterolemia (PMID: 8314561, 15701167, 18096825). This variant is present in population databases (rs775924858, gnomAD 0.0009%). 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). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.23
Cadd	Pathogenic	35
Dann	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	0.99	D
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
GERP RS		4.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.60		Position offset: 35
DS_DL_spliceai		1.0		Position offset: -1

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

Publications

LitVar

Other links and lift over

dbSNP: rs775924858; hg19: chr19-11224126;