rs1270618112

Variant names:

• chr19-11089355-ACTC-A
• rs1270618112
• NR_163945.1:n.302_304delGAG

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NR_163945.1(LDLR-AS1):​n.302_304delGAG variant causes a non coding transcript exon change. The variant allele was found at a frequency of 0.00000758 in 395,754 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000076 (0 hom.)
• Consequence: LDLR-AS1 NR_163945.1 non_coding_transcript_exon
• Clinical Significance: Uncertain significance reviewed by expert panel P:1 U:4
• Conservation: PhyloP100: 3.66

Genes affected

LDLR-AS1 (HGNC:54407): (LDLR antisense RNA 1) This gene represents a regulatory lncRNA that overlaps the 5' UTR and coding sequence of the LDLR (low density lipoprotein receptor) gene. This lncRNA overlaps LDLR in the antisense orientation, and has been shown to downregulate production of the low density lipoprotein receptor. [provided by RefSeq, Jul 2019]

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 Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LDLR	NM_000527.5	c.-193_-191delCTC		upstream_gene_variant		ENST00000558518.6	NP_000518.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LDLR	ENST00000558518.6	c.-193_-191delCTC		upstream_gene_variant		1	NM_000527.5	ENSP00000454071.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000758 AC: 3 AN: 395754 Hom.: 0 AF XY: 0.00000482 AC XY: 1 AN XY: 207338

Gnomad4 AFR exome AF: 0.0000930

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: 0.00000831

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.0000113

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1 Uncertain:4

Revision: reviewed by expert panel

Submissions by phenotype

Hypercholesterolemia, familial, 1 Pathogenic:1 Uncertain:3

Jan 11, 2024

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

-

Laboratorium voor Moleculaire Diagnostiek Experimentele Vasculaire Geneeskunde, Academisch Medisch Centrum

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: research

- -

Mar 01, 2016

Cardiovascular Research Group, Instituto Nacional de Saude Doutor Ricardo Jorge

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: curation;literature only

- -

Apr 28, 2023

ClinGen Familial Hypercholesterolemia Variant Curation Expert Panel

Significance: Uncertain significance

Review Status: reviewed by expert panel

Collection Method: curation

The NM_000527.5 (LDLR):c.-187_185del variant is classified as Uncertain significance - insufficient evidence for Familial Hypercholesterolemia by applying ACMG/AMP evidence codes PM2 and PS3_Supporting as defined by the ClinGen Familial Hypercholesterolemia Expert Panel LDLR-specific variant curation guidelines (specification version 1.2) on 28 April 2023. The supporting evidence is as follows: PM2: This variant is absent from gnomAD (gnomAD version 2.1.1). PS3_Supporting: Level 3 experiment, heterologous cells (HepG2) were used for luciferase assays, 8% reporter gene expression observed, PMID 9610768 (Peeters et al., 1998). -

Familial hypercholesterolemia Uncertain:1

Dec 25, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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 individual(s) with familial hypercholesterolemia (PMID: 9610768, 34756585, 36752612). This variant is also known as -92 (FH-Pedi-2). ClinVar contains an entry for this variant (Variation ID: 438314). Studies have shown that this variant alters LDLR gene expression (PMID: 9610768). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs1270618112; hg19: chr19-11200031;