1-55052735-G-A
Variant summary
Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate
The NM_174936.4(PCSK9):c.743G>A(p.Arg248His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000242 in 1,613,054 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign 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. R248C) has been classified as Uncertain significance.
Frequency
Consequence
NM_174936.4 missense
Scores
Clinical Significance
Conservation
Publications
- hypercholesterolemia, autosomal dominant, 3Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: ClinGen, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Ambry Genetics
- homozygous familial hypercholesterolemiaInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
Genome browser will be placed here
ACMG classification
Our verdict: Likely_benign. The variant received -2 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152238Hom.: 0 Cov.: 35 show subpopulations
GnomAD2 exomes AF: 0.0000603 AC: 15AN: 248896 AF XY: 0.0000666 show subpopulations
GnomAD4 exome AF: 0.0000260 AC: 38AN: 1460816Hom.: 1 Cov.: 82 AF XY: 0.0000316 AC XY: 23AN XY: 726738 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152238Hom.: 0 Cov.: 35 AF XY: 0.0000134 AC XY: 1AN XY: 74378 show subpopulations
ClinVar
Submissions by phenotype
Hypercholesterolemia, autosomal dominant, 3 Uncertain:2Benign:1
This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 248 of the PCSK9 protein (p.Arg248His). This variant is present in population databases (rs749573024, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with PCSK9-related conditions. ClinVar contains an entry for this variant (Variation ID: 375847). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt PCSK9 protein function with a negative predictive value of 80%. Experimental studies have shown that this missense change affects PCSK9 function (PMID: 29259136). 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. -
subject mutated among 2600 FH index cases screened = 1, family members = 4, without co-segregation / Software predictions: Benign -
This missense variant replaces arginine with histidine at codon 248 of the PCSK9 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). A functional study has shown that the variant causes increased proteolytic activity (PMID: 29259136). This variant has been reported in an individual suspected of having familial hypercholesterolemia (PMID: 32660911). This variant has also been identified in 15/248896 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
not specified Uncertain:1
Variant summary: PCSK9 c.743G>A (p.Arg248His) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 6e-05 in 248896 control chromosomes in the gnomAD database, including 1 homozygotes. The observed variant frequency is approximately 1.6 fold of the estimated maximal expected allele frequency for a pathogenic variant in PCSK9 causing Familial Hypercholesterolemia phenotype (3.8e-05). c.743G>A has been reported in the literature in individuals affected with Familial Hypercholesterolemia (Lamiquiz-Moneo_2021). These report(s) do not provide unequivocal conclusions about association of the variant with Familial Hypercholesterolemia. At least one publication reports experimental evidence evaluating an impact on protein function, and shows that this variant affects protein function (Chorba_2018). The following publications have been ascertained in the context of this evaluation (PMID: 29259136, 32660911). ClinVar contains an entry for this variant (Variation ID: 375847). Based on the evidence outlined above, the variant was classified as uncertain significance. -
Cardiovascular phenotype Uncertain:1
The p.R248H variant (also known as c.743G>A), located in coding exon 5 of the PCSK9 gene, results from a G to A substitution at nucleotide position 743. The arginine at codon 248 is replaced by histidine, an amino acid with highly similar properties. This amino acid position is not well conserved in available vertebrate species, and histidine is the reference amino acid in other vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Familial hypercholesterolemia Uncertain:1
This missense variant replaces arginine with histidine at codon 248 of the PCSK9 protein. Computational prediction tools indicate that this variant has a neutral impact on protein structure and function. A functional study has shown that the variant causes increased proteolytic activity (PMID: 29259136). This variant has been reported in one individual suspected to be affected with familial hypercholesterolemia (PMID: 32660911). This variant has also been identified in 15/248896 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at