chr19-11113415-T-C

Variant names:

• chr19-11113415-T-C
• rs879254863
• NM_000527.5:c.1324T>C

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PM1 PM2 PM5 PP2 PP3_Strong PP5

The NM_000527.5(LDLR):​c.1324T>C​(p.Tyr442His) 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. Y442C) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 29)
• Consequence: LDLR NM_000527.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3 U:1
• Conservation: PhyloP100: 7.92
• Publications: 4 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: Pathogenic. The variant received 12 ACMG points.

• PM1: In a hotspot region, there are 22 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 21 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 chr19-11113416-A-G is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 251787.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• 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.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.99
• PP5: Variant 19-11113415-T-C is Pathogenic according to our data. Variant chr19-11113415-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 251786.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000527.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	LDLR	NM_000527.5	MANE Select	c.1324T>C	p.Tyr442His	missense	Exon 9 of 18	NP_000518.1
	LDLR	NM_001195798.2		c.1324T>C	p.Tyr442His	missense	Exon 9 of 18	NP_001182727.1
	LDLR	NM_001195799.2		c.1201T>C	p.Tyr401His	missense	Exon 8 of 17	NP_001182728.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	LDLR	ENST00000558518.6	TSL:1 MANE Select	c.1324T>C	p.Tyr442His	missense	Exon 9 of 18	ENSP00000454071.1
	LDLR	ENST00000252444.10	TSL:1	c.1582T>C	p.Tyr528His	missense	Exon 9 of 18	ENSP00000252444.6
	LDLR	ENST00000558013.5	TSL:1	c.1324T>C	p.Tyr442His	missense	Exon 9 of 18	ENSP00000453346.1

Frequencies

GnomAD3 genomes Cov.: 29

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 29

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:3 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hypercholesterolemia, familial, 1 Pathogenic:2

Laboratorium voor Moleculaire Diagnostiek Experimentele Vasculaire Geneeskunde, Academisch Medisch Centrum

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: research

Mar 25, 2016

LDLR-LOVD, British Heart Foundation

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: literature only

Cardiovascular phenotype Pathogenic:1

Jul 07, 2021

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Y442H variant (also known as c.1324T>C), located in coding exon 9 of the LDLR gene, results from a T to C substitution at nucleotide position 1324. The tyrosine at codon 442 is replaced by histidine, an amino acid with similar properties, and is located in the YWTD motif of the LDLR type B repeat region. This variant, also referred to as p.Y421H, has been detected in individuals with definite or suspected familial hypercholesterolemia (FH); however, details were limited (Widhalm K et al. J Inherit Metab Dis, 2007 Apr;30:239-47; Ambry internal data). This variant has also been detected in a sudden death victim with atherosclerosis, ventricular dilation, and myocyte degeneration in the setting of a history of reported anabolic steroid abuse (Larsen MK et al. J Forensic Sci, 2012 May;57:658-62; Larsen MK et al. Forensic Sci Int, 2012 Jun;219:33-8). Based on internal structural analysis, this variant is predicted to be structurally disruptive to the LDLR type B repeat (Jeon H et al. Nat Struct Biol. 2001 Jun;8(6):499-504; Lo Surdo P et al. EMBO Rep. 2011 Dec;12(12):1300-5). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). This amino acid position is well 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.

Familial hypercholesterolemia Uncertain:1

Feb 15, 2020

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces tyrosine with histidine at codon 442 of the LDLR protein (p.Tyr442His). The tyrosine residue is highly conserved and there is a moderate physicochemical difference between tyrosine and histidine. 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. This variant is not present in population databases (ExAC no frequency). This variant has been observed in individual(s) with clinical features of familial hypercholesterolemia or premature atherosclerosis (PMID: 17347910, 22220933). This variant is also known as Y421H in the literature. ClinVar contains an entry for this variant (Variation ID: 251786). 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 disrupts the p.Tyr442 amino acid residue in LDLR. Other variant(s) that disrupt this residue have been observed in individuals with LDLR-related conditions (PMID: 15576851, 11857755), which suggests that this may be a clinically significant amino acid residue.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.77
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D
M_CAP	Pathogenic	0.96	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.1	H
PhyloP100		7.9
PrimateAI	Uncertain	0.63	T
PROVEAN	Pathogenic	-4.5	D
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.0040	D
Polyphen		1.0	D
Vest4		0.67
MutPred		0.97		Loss of catalytic residue at I441 (P = 0.041)
MVP		1.0
MPC		0.92
ClinPred		1.0	D
GERP RS		4.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.96
gMVP		0.98
Mutation Taster		=0/100	disease causing (ClinVar)

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: rs879254863; hg19: chr19-11224091;