1-226881909-T-G

Position:

• chr1-226881909-T-G

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_000447.3(PSEN2):​c.2T>G​(p.Met1?) variant causes a start lost change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: PSEN2 NM_000447.3 start_lost
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.45

Genes affected

PSEN2 (HGNC:9509): (presenilin 2) Alzheimer's disease (AD) patients with an inherited form of the disease carry mutations in the presenilin proteins (PSEN1 or PSEN2) or 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 act are protease enzymes. Two alternatively spliced transcript variants encoding different isoforms of PSEN2 have been identified. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PVS1: Start lost variant, no new inframe start found.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PSEN2	NM_000447.3	c.2T>G	p.Met1?	start_lost	4/13	ENST00000366783.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PSEN2	ENST00000366783.8	c.2T>G	p.Met1?	start_lost	4/13	5	NM_000447.3	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

PSEN2-related disorder Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

May 17, 2023

The PSEN2 c.2T>G variant is predicted to disrupt the translation initiation site (Start Loss). To our knowledge, this variant has not been reported in the literature or in a large population database (http://gnomad.broadinstitute.org), indicating this variant is rare. Most of the documented pathogenic variants in PSEN2 are missense variants and start loss variants in PSEN2 have not been reported. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.54
CADD	Benign	23
DANN	Uncertain	0.98
DEOGEN2	Benign	0.30	.;T;.;.;.;.
Eigen	Uncertain	0.41
Eigen_PC	Uncertain	0.43
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.90	D;D;D;D;.;T
M_CAP	Pathogenic	0.83	D
MetaRNN	Pathogenic	0.89	D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationTaster	Benign	1.0	D;D;N;N;N
PROVEAN	Pathogenic	-6.0	D;N;N;N;N;.
REVEL	Pathogenic	0.82
Sift	Pathogenic	0.0	.;D;D;D;D;.
Sift4G	Pathogenic	0.0	.;D;D;D;D;D
Polyphen		0.94	.;P;.;.;.;.
Vest4		0.92, 0.92, 0.75, 0.81
MutPred		0.55		Gain of methylation at M1 (P = 0.0198);Gain of methylation at M1 (P = 0.0198);Gain of methylation at M1 (P = 0.0198);Gain of methylation at M1 (P = 0.0198);.;.;
MVP		0.99
ClinPred		0.99	D
GERP RS		5.2
Varity_R		0.92
gMVP		0.38

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.21		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.21		Position offset: -21

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr1-227069610;