19-11102756-T-G

Position:

• chr19-11102756-T-G

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM1 PM2 PM5 PP3_Strong PP5

The NM_000527.5(LDLR):​c.283T>G​(p.Cys95Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. C95F) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 31)
• Consequence: LDLR NM_000527.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4 U:1
• Conservation: PhyloP100: 7.97

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 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PM1: In a strand (size 2) in uniprot entity LDLR_HUMAN there are 8 pathogenic changes around while only 0 benign (100%) 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 chr19-11102757-G-T is described in Lovd as [Likely_pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.996
• PP5: Variant 19-11102756-T-G is Pathogenic according to our data. Variant chr19-11102756-T-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 251112.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=1, Pathogenic=2, Likely_pathogenic=1}. Variant chr19-11102756-T-G is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LDLR	NM_000527.5	c.283T>G	p.Cys95Gly	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	c.283T>G	p.Cys95Gly	missense_variant	3/18	1	NM_000527.5	ENSP00000454071.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:4 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hypercholesterolemia, familial, 1 Pathogenic:2 Uncertain:1

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

Familial hypercholesterolemia Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jul 19, 2017	This variant affects a cysteine residue located within an LDLRA domain 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 domains affecting cysteine residues are overrepresented among patients with hypercholesterolemia (PMID: 18325082). For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has been reported in multiple unrelated individuals affected with familial hypercholesterolemia (PMID: 15241806, 18718593, 19007590, 21955034). This variant is also known as p.Cys74Gly in the literature. ClinVar contains an entry for this variant (Variation ID: 251112). This variant is not present in population databases (ExAC no frequency). This sequence change replaces cysteine with glycine at codon 95 of the LDLR protein (p.Cys95Gly). The cysteine residue is highly conserved and there is a large physicochemical difference between cysteine and glycine. -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jun 04, 2024	Variant summary: LDLR c.283T>G (p.Cys95Gly) 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 251478 control chromosomes. c.283T>G has been reported in the literature in multiple individuals affected with Familial Hypercholesterolemia (Cenarro_1997, Tada_2020). These data indicate that the variant is very likely to be associated with disease. 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: 10206683, 32331935). ClinVar contains an entry for this variant (Variation ID: 251112). Based on the evidence outlined above, the variant was classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.59
CADD	Uncertain	25
DANN	Uncertain	0.98
DEOGEN2	Pathogenic	0.98	D;.;.;.;.
Eigen	Pathogenic	0.93
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D;D;D;D;D
M_CAP	Pathogenic	0.92	D
MetaRNN	Pathogenic	1.0	D;D;D;D;D
MetaSVM	Pathogenic	0.91	D
MutationAssessor	Pathogenic	4.7	H;.;H;H;H
PrimateAI	Uncertain	0.49	T
PROVEAN	Pathogenic	-11	D;D;D;D;D
REVEL	Pathogenic	0.95
Sift	Uncertain	0.0020	D;D;D;D;D
Sift4G	Uncertain	0.0030	D;D;D;D;D
Polyphen		1.0	D;.;.;.;.
Vest4		0.98
MutPred		0.94		Loss of stability (P = 0.0129);Loss of stability (P = 0.0129);Loss of stability (P = 0.0129);Loss of stability (P = 0.0129);Loss of stability (P = 0.0129);
MVP		1.0
MPC		0.91
ClinPred		1.0	D
GERP RS		5.7
Varity_R		1.0
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

Other links and lift over

dbSNP: rs879254456; hg19: chr19-11213432; COSMIC: COSV52941577; COSMIC: COSV52941577;