ClinVar Genomic variation as it relates to human health

The NM_000527.5 (LDLR):c.1920C>T (p.Asn640=) variant is classified as Benign for Familial Hypercholesterolemia by applying evidence codes (BA1, BP4, BP7, BS3_Supporting) as defined by the ClinGen Familial Hypercholesterolemia Expert Panel LDLR-specific variant curation guidelines (https://doi.org/10.1016/j.gim.2021.09.012). The supporting evidence is as follows: BA1: FAF=0.03838 in Ashkenazi Jewish population in gnomAD (gnomAD 2.1.1). BP4: No REVEL, splicing evaluation required. A) not in limit. B) does not create AG or GT. C) there is a GT nearby. Var cryptic score/Wt cryptic score=0.69, it is not above 1.1, and Var cryptic score/Wt score= -0.80, it is not above 0.9. Variant is not predicted to alter splicing. BP7: Variant is synonymous and meets BP4. BS3_Supporting: Level 3 assay with heterozygous patients’ lymphocytes, RNA assays shown normal LDLR transcripts, reported by Medeiros et al, 2016, from Instituto Nacional de Saude Doutor Ricardo Jorge, Lisbon, Portugal, PMID 26020417. Functional data is consistent with no damaging effect. PP4, PS4 not met: Variant did not meet PM2. PP1 not met: There are 2 relatives without the variant had LDL-C <50th percentile in 1 family, however the index case did not meet Simon Broome criteria for FH diagnosis, reported in VCI from Cardiovascular Research Group,Instituto Nacional de Saude Doutor Ricardo Jorge. BS4 not met: There are 2 relatives without the variant had LDL-C >75th percentile in 1 family, however the index case did not meet Simon Broome criteria for FH diagnosis, and there is no instance where an unaffected family member carries the variant, reported in VCI from Cardiovascular Research Group,Instituto Nacional de Saude Doutor Ricardo Jorge. BP2 not met: Variant identified in an index case with heterozygous FH phenotype and an unspecified LDLR variant with unknown pathogenicity and phase, reported in VCI from Service de Biochimie et de Biologie Moléculaire, Hospices Civils de Lyon, Lyon, France.

0/95 non-FH individuals

does not meet required criteria

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease.

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance.

This alteration is classified as benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity.

LDLR: BP4, BP7