Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1PM2PP3_ModeratePP5_Moderate
The NM_000501.4(ELN):c.1153delG(p.Ala385fs) variant causes a frameshift, splice region change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 1/1 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★). Variant results in nonsense mediated mRNA decay.
ELN (HGNC:3327): (elastin) This gene encodes a protein that is one of the two components of elastic fibers. Elastic fibers comprise part of the extracellular matrix and confer elasticity to organs and tissues including the heart, skin, lungs, ligaments, and blood vessels. The encoded protein is rich in hydrophobic amino acids such as glycine and proline, which form mobile hydrophobic regions bounded by crosslinks between lysine residues. Degradation products of the encoded protein, known as elastin-derived peptides or elastokines, bind the elastin receptor complex and other receptors and stimulate migration and proliferation of monocytes and skin fibroblasts. Elastokines can also contribute to cancer progression. Deletions and mutations in this gene are associated with supravalvular aortic stenosis (SVAS) and autosomal dominant cutis laxa. [provided by RefSeq, Aug 2017]
Verdict is Pathogenic. Variant got 14 ACMG points.
PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP3
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
PP5
Variant 7-74056269-AG-A is Pathogenic according to our data. Variant chr7-74056269-AG-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 163392.Status of the report is criteria_provided_single_submitter, 1 stars.
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing
The Ala385fs variant has not been reported in the literature nor previously iden tified by our laboratory. However, this variant is predicted to cause a frameshi ft, which alters the protein's amino acid sequence beginning at codon 385 and le ads to a premature stop codon 89 amino acids downstream. This alteration is pred icted to lead to a truncated or absent protein and therefore, to a heterozygous loss of function of the elastin (ELN) gene. Loss of function variants in ELN are an established mechanism of disease in SVAS (Human Gene Mutation Database, HGMD ), which is consistent with this individual?s clinical features. In summary, the Ala385fs variant is likely to be pathogenic. -