chr19-11113431-C-T

Variant names:

• chr19-11113431-C-T
• rs879254870
• NM_000527.5:c.1340C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 7P and 1B. PM1 PM2 PM5 PP2 BP4

The NM_000527.5(LDLR):​c.1340C>T​(p.Ser447Phe) 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 benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S447C) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 29)
• Consequence: LDLR NM_000527.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.02
• Publications: 0 publications found

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]

MIR6886 (HGNC:50121): (microRNA 6886) microRNAs (miRNAs) are short (20-24 nt) non-coding RNAs that are involved in post-transcriptional regulation of gene expression in multicellular organisms by affecting both the stability and translation of mRNAs. miRNAs are transcribed by RNA polymerase II as part of capped and polyadenylated primary transcripts (pri-miRNAs) that can be either protein-coding or non-coding. The primary transcript is cleaved by the Drosha ribonuclease III enzyme to produce an approximately 70-nt stem-loop precursor miRNA (pre-miRNA), which is further cleaved by the cytoplasmic Dicer ribonuclease to generate the mature miRNA and antisense miRNA star (miRNA*) products. The mature miRNA is incorporated into a RNA-induced silencing complex (RISC), which recognizes target mRNAs through imperfect base pairing with the miRNA and most commonly results in translational inhibition or destabilization of the target mRNA. The RefSeq represents the predicted microRNA stem-loop. [provided by RefSeq, Sep 2009]

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 20 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 17 uncertain 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 chr19-11113431-C-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 251797.
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 678 curated pathogenic missense variants (we use a threshold of 10). The gene has 92 curated benign missense variants. Gene score misZ: 0.12407 (below the threshold of 3.09). Trascript score misZ: 0.59338 (below the threshold of 3.09). GenCC associations: The gene is linked to hypercholesterolemia, familial, 1, homozygous familial hypercholesterolemia.
• BP4: Computational evidence support a benign effect (MetaRNN=0.40829536).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LDLR	NM_000527.5	c.1340C>T	p.Ser447Phe	missense_variant	Exon 9 of 18	ENST00000558518.6	NP_000518.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LDLR	ENST00000558518.6	c.1340C>T	p.Ser447Phe	missense_variant	Exon 9 of 18	1	NM_000527.5	ENSP00000454071.1

Frequencies

GnomAD3 genomes Cov.: 29

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 29

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial hypercholesterolemia Uncertain:1

Jan 03, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant has not been reported in the literature in individuals affected with LDLR-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces serine, which is neutral and polar, with phenylalanine, which is neutral and non-polar, at codon 447 of the LDLR protein (p.Ser447Phe). 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. 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on LDLR protein function.

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.42
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.16
CADD	Benign	22
DANN	Uncertain	0.98
DEOGEN2	Uncertain	0.76	D;.;.;.;.;.
Eigen	Benign	-0.24
Eigen_PC	Benign	-0.16
LIST_S2	Uncertain	0.92	D;D;D;D;D;D
M_CAP	Pathogenic	0.39	D
MetaRNN	Benign	0.41	T;T;T;T;T;T
MetaSVM	Uncertain	0.67	D
MutationAssessor	Uncertain	2.4	M;.;.;.;.;M
PhyloP100		1.0
PrimateAI	Benign	0.47	T
PROVEAN	Benign	-1.6	N;N;N;N;N;N
Sift	Benign	0.14	T;T;T;T;T;T
Sift4G	Benign	0.57	T;T;T;T;T;T
Vest4		0.31
ClinPred		0.49	T
GERP RS		4.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.50
gMVP		0.98
Mutation Taster		=28/72	disease causing

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

Other links and lift over

dbSNP: rs879254870; hg19: chr19-11224107;