Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM1PM2PM5PP2PP3_StrongPP5
The NM_000021.4(PSEN1):c.749T>C(p.Leu250Ser) 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. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L250V) has been classified as Uncertain significance.
PSEN1 (HGNC:9508): (presenilin 1) Alzheimer's disease (AD) patients with an inherited form of the disease carry mutations in the presenilin proteins (PSEN1; PSEN2) or in the amyloid precursor protein (APP). These disease-linked mutations result in increased production of the longer form of amyloid-beta (main component of amyloid deposits found in AD brains). Presenilins are postulated to regulate APP processing through their effects on gamma-secretase, an enzyme that cleaves APP. Also, it is thought that the presenilins are involved in the cleavage of the Notch receptor, such that they either directly regulate gamma-secretase activity or themselves are protease enzymes. Several alternatively spliced transcript variants encoding different isoforms have been identified for this gene, the full-length nature of only some have been determined. [provided by RefSeq, Aug 2008]
Verdict is Pathogenic. Variant got 12 ACMG points.
PM1
?
PM1 - Located in a mutational hot spot and/or critical and well-established functional domain (e.g., active site of an enzyme) without benign variation
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 2 uncertain in NM_000021.4
PM2
?
PM2 - Absent from controls (or at extremely low frequency if recessive) in Exome Sequencing Project, 1000 Genomes Project, or Exome Aggregation Consortium
Very rare variant in population databases, with high coverage;
PM5
?
PM5 - Novel missense change at an amino acid residue where a different missense change determined to be pathogenic has been seen before
Other missense variant is known to change same aminoacid residue: Variant chr14-73192845-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 1453682.Status of the report is criteria_provided_single_submitter, 1 stars.
PP2
?
PP2 - Missense variant in a gene that has a low rate of benign missense variation and in which missense variants are a common mechanism of disease
Missense variant where missense usually causes diseases, PSEN1
PP3
?
PP3 - Multiple lines of computational evidence support a deleterious effect on the gene or gene product (conservation, evolutionary, splicing impact, etc.)
MetaRNN computational evidence supports a deleterious effect, 0.965
PP5
?
PP5 - Reputable source recently reports variant as pathogenic, but the evidence is not available to the laboratory to perform an independent evaluation
Variant 14-73192844-T-C is Pathogenic according to our data. Variant chr14-73192844-T-C is described in ClinVar as [Pathogenic]. Clinvar id is 18138.Status of the report is no_assertion_criteria_provided, 0 stars. Variant chr14-73192844-T-C is described in Lovd as [Pathogenic].