chr19-11111632-G-T

Position:

• chr19-11111632-G-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PS1 PM1 PM2 PM5 PP3_Moderate

The ENST00000558518.6(LDLR):​c.1179G>T​(p.Lys393Asn) variant causes a missense change involving the alteration of a non-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 Uncertain significance (★). Another nucleotide change resulting in same amino acid change has been previously reported as Likely pathogenicin ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K393E) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 31)
• Consequence: LDLR ENST00000558518.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.0310

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 12 ACMG points.

• PS1: Transcript ENST00000558518.6 (LDLR) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar as 251700
• PM1: In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 11 uncertain in ENST00000558518.6
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr19-11111630-A-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 403636.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.864

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LDLR	NM_000527.5	c.1179G>T	p.Lys393Asn	missense_variant	8/18	ENST00000558518.6	NP_000518.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LDLR	ENST00000558518.6	c.1179G>T	p.Lys393Asn	missense_variant	8/18	1	NM_000527.5	ENSP00000454071	P3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial hypercholesterolemia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 17, 2019

This sequence change replaces lysine with asparagine at codon 393 of the LDLR protein (p.Lys393Asn). The lysine residue is highly conserved and there is a moderate physicochemical difference between lysine and asparagine. 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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has been observed in an individual with clinical features of familial hypercholesterolemia (Invitae). This variant is not present in population databases (ExAC no frequency). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.86
BayesDel_addAF	Pathogenic	0.20	D
BayesDel_noAF	Uncertain	0.040
CADD	Benign	20
DANN	Uncertain	0.98
DEOGEN2	Pathogenic	0.90	D;.;.;.;.;.
Eigen	Benign	-0.31
Eigen_PC	Benign	-0.42
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.97	D;D;D;D;D;D
M_CAP	Pathogenic	0.86	D
MetaRNN	Pathogenic	0.86	D;D;D;D;D;D
MetaSVM	Pathogenic	0.92	D
MutationAssessor	Uncertain	2.5	M;.;.;.;.;M
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.63	T
PROVEAN	Pathogenic	-4.7	D;D;D;D;D;D
REVEL	Uncertain	0.60
Sift	Uncertain	0.0010	D;D;D;D;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D;D;D
Polyphen		1.0	D;.;.;.;.;.
Vest4		0.59
MutPred		0.46		Loss of methylation at K393 (P = 0.0011);Loss of methylation at K393 (P = 0.0011);.;.;.;Loss of methylation at K393 (P = 0.0011);
MVP		1.0
MPC		0.84
ClinPred		0.98	D
GERP RS		1.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.92
gMVP		0.98

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.16		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: rs879254816; hg19: chr19-11222308;