chr19-11105319-C-G

Position:

• chr19-11105319-C-G

Variant summary

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

The NM_000527.5(LDLR):​c.413C>G​(p.Ser138*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,550 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 Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: LDLR NM_000527.5 stop_gained
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 1.71

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 19-11105319-C-G is Pathogenic according to our data. Variant chr19-11105319-C-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 251208.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr19-11105319-C-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LDLR	NM_000527.5	c.413C>G	p.Ser138*	stop_gained	4/18	ENST00000558518.6	NP_000518.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LDLR	ENST00000558518.6	c.413C>G	p.Ser138*	stop_gained	4/18	1	NM_000527.5	ENSP00000454071.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251202 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135850

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000653

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461550 Hom.: 0 Cov.: 33 AF XY: 0.00000275 AC XY: 2 AN XY: 727106

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: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Homozygous familial hypercholesterolemia Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Apr 16, 2019

The p.Ser138X variant in LDLR has been reported in one individual with familial hypercholesterolemia (FH; Usifo 2012). It has also been reported by other clinical laboratories in ClinVar (Variation ID: 251208) and has been identified in 0.007% (2/30616) of South Asian chromosomes by gnomAD (http://gnomad.broadinstitute.org). This frequency is low enough to be consistent with the frequency of FH in the general population. This nonsense variant leads to a premature termination codon at position 138, 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, although additional studies are required to fully establish its clinical significance, this variant meets criteria to be classified as likely pathogenic for autosomal dominant FH. ACMG/AMP Criteria applied: PVS1, PM2. -

Hypercholesterolemia, familial, 1 Pathogenic:1

Pathogenic, criteria provided, single submitter

literature only

LDLR-LOVD, British Heart Foundation

Mar 25, 2016

- -

Familial hypercholesterolemia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 20, 2022

This premature translational stop signal has been observed in individual(s) with familial hypercholesterolemia (PMID: 22881376, 32331935). This variant is present in population databases (rs755799528, gnomAD 0.006%). This sequence change creates a premature translational stop signal (p.Ser138*) 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). For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 251208). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.48
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Pathogenic	0.88
Eigen_PC	Pathogenic	0.67
FATHMM_MKL	Uncertain	0.95	D
Vest4		0.73
GERP RS		4.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.2

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: rs755799528; hg19: chr19-11215995;