rs879254368

Positions:

• chr19-11089400-C-A

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 10P and 1B. PM2 PP5_Very_Strong BP4

The NR_163945.1(LDLR-AS1):​n.260G>T variant causes a non coding transcript exon change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000208 in 480,098 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: LDLR-AS1 NR_163945.1 non_coding_transcript_exon
• Clinical Significance: Likely pathogenic reviewed by expert panel P:3 U:1
• Conservation: PhyloP100: 0.474

Genes affected

LDLR-AS1 (HGNC:):

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 Likely_pathogenic. Variant got 9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 19-11089400-C-A is Pathogenic according to our data. Variant chr19-11089400-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 250946.Status of the report is reviewed_by_expert_panel, 3 stars.
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.1). . Strength limited to SUPPORTING due to the PP5.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LDLR-AS1	NR_163945.1	n.260G>T		non_coding_transcript_exon_variant	1/1
		n.11089400C>A		intergenic_region

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LDLR	ENST00000559340.2	n.-149C>A		upstream_gene_variant		5		ENSP00000453696.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000208 AC: 1 AN: 480098 Hom.: 0 Cov.: 6 AF XY: 0.00 AC XY: 0 AN XY: 251374

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000484

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:3 Uncertain:1

Revision: reviewed by expert panel

Submissions by phenotype

Hypercholesterolemia, familial, 1 Pathogenic:2 Uncertain:1

Likely pathogenic, criteria provided, single submitter	clinical testing	Molecular Genetics Laboratory, Centre for Cardiovascular Surgery and Transplantation	Nov 05, 2016	Disrupt Sterol Regulatory Element sequence. -
Uncertain significance, criteria provided, single submitter	literature only	LDLR-LOVD, British Heart Foundation	Mar 25, 2016	- -
Likely pathogenic, reviewed by expert panel	curation	ClinGen Familial Hypercholesterolemia Variant Curation Expert Panel	Aug 29, 2022	The NM_000527.4(LDLR):c.-149C>A variant is classified as Likely pathogenic for Familial Hypercholesterolemia by applying evidence codes (PM2, PS4, PP4, PP1_moderate) as defined by the ClinGen Familial Hypercholesterolemia Expert Panel LDLR-specific variant curation guidelines (https://doi.org/10.1101/2021.03.17.21252755). The supporting evidence is as follows: PM2 - This variant is absent from gnomAD (gnomAD v2.1.1), so PM2 is Met. PS4 - Variant meets PM2 and is identified in 10 unrelated index cases who fulfill Simon Broome criteria for FH (4 definite FH and 6 possible FH) from Molecular Genetics Laboratory (Centre for Cardiovascular Surgery and Transplantation)(PMID: 28379029), so PS4 is Met. PP4 - Variant meets PM2 and is identified in 10 unrelated index cases who fulfill Simon Broome criteria for FH (see PS4 for details), so PP4 is Met. PP1_Moderate - Variant segregates with FH phenotype in 4 informative meiosis from 3 families from Molecular Genetics Laboratory (Centre for Cardiovascular Surgery and Transplantation)(PMID: 28379029), so PP1_Moderate is Met. -

Familial hypercholesterolemia Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 15, 2024

This variant occurs in a non-coding region of the LDLR gene. It does not change the encoded amino acid sequence of the LDLR protein. This variant is not present in population databases (gnomAD no frequency). This variant has been observed in individuals with familial hypercholesterolemia (PMID: 22698793, 28379029). ClinVar contains an entry for this variant (Variation ID: 250946). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.10
CADD	Benign	17
DANN	Benign	0.95

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: rs879254368; hg19: chr19-11200076; COSMIC: COSV52944843; COSMIC: COSV52944843;