Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP2PP3
The NM_000021.4(PSEN1):c.998A>T(p.Asp333Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,150 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.
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 Likely_pathogenic. Variant got 6 ACMG points.
PM1
In a region_of_interest Required for interaction with CTNNB1 (size 128) in uniprot entity PSN1_HUMAN there are 38 pathogenic changes around while only 1 benign (97%) in NM_000021.4
PM2
Very rare variant in population databases, with high coverage;
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, 0.814