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 Pathogenic.
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
In a transmembrane_region Helical (size 23) in uniprot entity PSN1_HUMAN there are 26 pathogenic changes around while only 0 benign (100%) in NM_000021.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr14-73192843-T-G is described in Lovd as [Pathogenic].
PP2
Missense variant in the PSEN1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 113 curated pathogenic missense variants (we use a threshold of 10). The gene has 14 curated benign missense variants. Gene score misZ: 2.1558 (below the threshold of 3.09). Trascript score misZ: 3.0986 (above the threshold of 3.09). GenCC associations: The gene is linked to acne inversa, familial, 3, dilated cardiomyopathy, Alzheimer disease 3, early-onset autosomal dominant Alzheimer disease, semantic dementia, Pick disease, familial isolated dilated cardiomyopathy, dilated cardiomyopathy 1U, behavioral variant of frontotemporal dementia.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.965
PP5
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].