rs879254439
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
Consequence
NM_000527.5 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Pathogenic. Variant got 18 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
LDLR | NM_000527.5 | 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 | c.223T>A | p.Cys75Ser | missense_variant | 3/18 | 1 | NM_000527.5 | ENSP00000454071.1 |
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152182Hom.: 0 Cov.: 31
GnomAD4 exome AF: 6.84e-7 AC: 1AN: 1461678Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0AN XY: 727138
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152182Hom.: 0 Cov.: 31 AF XY: 0.0000134 AC XY: 1AN XY: 74354
ClinVar
Submissions by phenotype
Hypercholesterolemia, familial, 1 Pathogenic:3
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 - |
Likely pathogenic, criteria provided, single submitter | literature only | LDLR-LOVD, British Heart Foundation | Mar 25, 2016 | - - |
Pathogenic, criteria provided, single submitter | clinical testing | Victorian Clinical Genetics Services, Murdoch Childrens Research Institute | Sep 02, 2022 | Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with familial hypercholesterolaemia 1 (FH; MIM#143890). (I) 0108 - This gene is associated with both recessive and dominant disease. Variants have been reported in heterozygous, compound heterozygous and homozygous states, with recessive disease being more severe (OMIM, PMID: 10978268). (I) 0112 - The condition associated with this gene has incomplete penetrance (PMID: 24404629). (I) 0200 - Variant is predicted to result in a missense amino acid change from cysteine to serine. (I) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD <0.01 (v3) (1 heterozygote, 0 homozygotes). (SP) 0501 - Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change. (SP) 0601 - Variant is located in the well-established functional LDLR-A domain and affects a cysteine residue. Cysteine residues in the LDLR-A domains have been shown to form disulphide bonds which are critical for the structure and stability of the protein (DECIPHER, NCBI, PMIDs: 7548065, 15952897). (SP) 0703 - Other missense variants comparable to the one identified in this case have moderate previous evidence for pathogenicity. p.(Cys75Tyr) has been classified as pathogenic by a clinical laboratory in ClinVar, and p.(Cys75Trp) has been observed in an individual with FH (PMID: 17094996). (SP) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. This variant has been classified as pathogenic and likely pathogenic by clinical laboratories in ClinVar, and has been observed in two heterozygous individuals with FH in the literature (PMIDs: 10089940, 34327453). (SP) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign - |
Familial hypercholesterolemia Pathogenic:3
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. - |
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. - |
not provided Pathogenic:2
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) - |
Likely pathogenic, criteria provided, single submitter | clinical testing | Quest Diagnostics Nichols Institute San Juan Capistrano | Dec 04, 2023 | The LDLR c.223T>A (p.Cys75Ser) variant has been reported in the published literature in individuals with hypercholesterolemia (PMID: 10089940 (1998), 9676383 (1998), PMID: 34037665 (2021)) as well as in pediatric individuals with hypercholesterolemia (PMID: 26361156 (2015), 35913489 (2022)). This variant affects one of the cysteine residues located in LDL Receptor Domain Class A (LDLa) repeat 2 that form disulfide bonds causing a LDLR protein folding defect (PMID: 34906454 (2022)). This variant has not been reported in large, multi-ethnic general populations (Genome Aggregation Database, http://gnomad.broadinstitute.org). Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded predictions that this variant is damaging. Based on the available information, this variant is classified as likely pathogenic. - |
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:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at