rs879254439

Positions:

chr19-11102696-T-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_000527.5(LDLR):c.223T>A(p.Cys75Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,860 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. C75W) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

LDLR
NM_000527.5 missense

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:7

Conservation

PhyloP100: 7.90

Variant links:

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]

LDLR links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PM1

In a disulfide_bond (size 14) in uniprot entity LDLR_HUMAN there are 12 pathogenic changes around while only 1 benign (92%) in NM_000527.5

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr19-11102698-T-G is described in Lovd as [Likely_pathogenic].

PP3

MetaRNN computational evidence supports a deleterious effect, 0.992

PP5

Variant 19-11102696-T-A is Pathogenic according to our data. Variant chr19-11102696-T-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 251079.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr19-11102696-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 linkuse as main transcript	c.223T>A	p.Cys75Ser	missense_variant	3/18	ENST00000558518.6	NP_000518.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LDLR	ENST00000558518.6 linkuse as main transcript	c.223T>A	p.Cys75Ser	missense_variant	3/18	1	NM_000527.5	ENSP00000454071	P3	P01130-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152182

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461678

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

727138

show subpopulations

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:

8.99e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152182

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74354

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Familial hypercholesterolemia

Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Oct 04, 2023	This sequence change replaces cysteine, which is neutral and slightly polar, with serine, which is neutral and polar, at codon 75 of the LDLR protein (p.Cys75Ser). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with hypercholesterolemia (PMID: 10089940; Invitae). This variant is also known as C54S. ClinVar contains an entry for this variant (Variation ID: 251079). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt LDLR protein function. This variant affects a cysteine residue located within an LDLRA or epidermal-growth-factor (EGF)-like domains of the LDLR protein. Cysteine residues in these domains have been shown to be involved in the formation of disulfide bridges, which are critical for protein structure and stability (PMID: 7548065, 7603991, 7979249). In addition, missense substitutions within the LDLRA and EGF-like domains affecting cysteine residues are overrepresented among patients with hypercholesterolemia (PMID: 18325082). This variant disrupts the p.Cys75 amino acid residue in LDLR. Other variant(s) that disrupt this residue have been observed in individuals with LDLR-related conditions (PMID: 9676383, 10089940, 12124988, 17094996; Invitae), which suggests that this may be a clinically significant amino acid residue. For these reasons, this variant has been classified as Pathogenic. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jul 09, 2024	Variant summary: LDLR c.223T>A (p.Cys75Ser) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 251492 control chromosomes. c.223T>A has been reported in the literature in the heterozygous state in multiple individuals and in the presumed compound heterozygous state in at least 1 indivdiual affected with Familial Hypercholesterolemia (example, Cuchel_2023, Emi_1998, Klancar_2015, Sturm_2021, Sustar_2022). These data indicate that the variant may be associated with disease. Additionally, a different missense variant at the same codon (p.Cys75Tyr) has been classified as Likely Pathogenic/Pathogenic by all laboratories in ClinVar, suggesting this residue is clinically important. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 37119068, 10089940, 26361156, 34037665, 35913489). ClinVar contains an entry for this variant (Variation ID: 251079). Based on the evidence outlined above, the variant was classified as likely pathogenic. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 12, 2019	This missense variant (also known as p.Cys54Ser in the mature protein) is located in the second LDLR type A repeat of the ligand binding domain of LDLR protein. Computational prediction tools and conservation analyses suggest that this variant may have deleterious impact on the protein function. Computational splicing tools suggest that this variant may not impact the RNA splicing. Although functional assays have not been performed for this variant, it changes one of the functionally critical cysteine residues that form intra-repeat disulfide bonds in the ligand binding domain (PMID: 15952897) and is expected to have deleterious impact on the LDLR protein folding and stability. This variant has been identified in an individual diagnosed with familial hypercholesterolemia in U.S. (PMID: 10089940). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Based on available evidence, this variant is classified as Likely Pathogenic. -

Hypercholesterolemia, familial, 1

Pathogenic:2

Likely pathogenic, criteria provided, single submitter	literature only	LDLR-LOVD, British Heart Foundation	Mar 25, 2016	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Apr 08, 2020	proposed classification - variant undergoing re-assessment, contact laboratory -

not provided

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Apr 02, 2024

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Also known as p.(C54S); This variant is associated with the following publications: (PMID: 35913489, 34037665, 2988123, 12459547, 10089940) -

Cardiovascular phenotype

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 04, 2023

The p.C75S variant (also known as c.223T>A), located in coding exon 3 of the LDLR gene, results from a T to A substitution at nucleotide position 223. The cysteine at codon 75 is replaced by serine, an amino acid with dissimilar properties. Pathogenic LDLR mutations that result in the substitution or generation of cysteine residues within the cysteine-rich LDLR class A repeats and EGF-like domains are common in familial hypercholesterolemia (FH) (Villéger L et al. Hum Mutat. 2002;20(2):81-7). This particular cysteine alteration (also referred to as C54S) has been described in a proband with LDL-C level of 298mg/dL, in a Slovenian pediatric hypercholesterolemia cohort, and in additional probands referred for FH genetic testing (Emi M et al. Jpn Heart J. 1998;39(6):785-789; Klanar G et al. J. Am. Coll. Cardiol. 2015;66(11):1250-1257; external communication). Internal structural analysis indicates this alteration eliminates a disulfide bond critical for the structural integrity of LDLR class A repeat 2 (Ambry internal data). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.99

BayesDel_addAF

Pathogenic

0.58

BayesDel_noAF

Pathogenic

0.60

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.97

D;.;.;.;.

Eigen

Pathogenic

1.0

Eigen_PC

Pathogenic

0.93

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Benign

0.83

T;T;T;D;T

M_CAP

Pathogenic

0.92

MetaRNN

Pathogenic

0.99

D;D;D;D;D

MetaSVM

Pathogenic

0.91

MutationAssessor

Pathogenic

4.0

H;.;H;H;H

MutationTaster

Benign

1.0

D;D;D;D;D;D;D

PrimateAI

Benign

0.48

PROVEAN

Pathogenic

-9.2

D;D;D;D;D

REVEL

Pathogenic

0.97

Sift

Pathogenic

0.0

D;D;D;D;D

Sift4G

Pathogenic

0.0

D;D;D;D;D

Polyphen

0.97

D;.;.;.;.

Vest4

0.93

MutPred

0.90

Gain of glycosylation at C75 (P = 0.0551);Gain of glycosylation at C75 (P = 0.0551);Gain of glycosylation at C75 (P = 0.0551);Gain of glycosylation at C75 (P = 0.0551);Gain of glycosylation at C75 (P = 0.0551);

MVP

1.0

MPC

0.90

ClinPred

1.0

GERP RS

5.7

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.99

gMVP

1.0

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over