21-25881080-G-T

Variant summary

Our verdict is Benign. Variant got -14 ACMG points: 0P and 14B. BP4_Strong BP6_Moderate BA1

The NM_000484.4(APP):c.*590C>A variant causes a 3 prime UTR change. The variant allele was found at a frequency of 0.00841 in 156,406 control chromosomes in the GnomAD database, including 21 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.0086 (21 hom., cov: 32)
  • Exomes 𝑓: 0.00024 (0 hom.)
• Consequence: APP NM_000484.4 3_prime_UTR
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 3.59

Genes affected

APP (HGNC:620): (amyloid beta precursor protein) This gene encodes a cell surface receptor and transmembrane precursor protein that is cleaved by secretases to form a number of peptides. Some of these peptides are secreted and can bind to the acetyltransferase complex APBB1/TIP60 to promote transcriptional activation, while others form the protein basis of the amyloid plaques found in the brains of patients with Alzheimer disease. In addition, two of the peptides are antimicrobial peptides, having been shown to have bacteriocidal and antifungal activities. Mutations in this gene have been implicated in autosomal dominant Alzheimer disease and cerebroarterial amyloidosis (cerebral amyloid angiopathy). Multiple transcript variants encoding several different isoforms have been found for this gene. [provided by RefSeq, Aug 2014]

ACMG classification

Verdict is Benign. Variant got -14 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.66).
• BP6: Variant 21-25881080-G-T is Benign according to our data. Variant chr21-25881080-G-T is described in ClinVar as [Likely_benign]. Clinvar id is 339624.Status of the report is criteria_provided_single_submitter, 1 stars.
• BA1: GnomAdExome4 highest subpopulation (AFR) allele frequency = 0.125 is higher than 0.05.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
APP	NM_000484.4	c.*590C>A		3_prime_UTR_variant	18/18	ENST00000346798.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
APP	ENST00000346798.8	c.*590C>A		3_prime_UTR_variant	18/18	1	NM_000484.4

Frequencies

GnomAD3 genomes AF: 0.00857 AC: 1304 AN: 152142 Hom.: 20 Cov.: 32

Gnomad AFR AF: 0.0302

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00216

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00633

Gnomad NFE AF: 0.0000735

Gnomad OTH AF: 0.00526

GnomAD4 exome AF: 0.000241 AC: 1 AN: 4146 Hom.: 0 Cov.: 0 AF XY: 0.000444 AC XY: 1 AN XY: 2252

Gnomad4 AFR exome AF: 0.125

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00864 AC: 1315 AN: 152260 Hom.: 21 Cov.: 32 AF XY: 0.00854 AC XY: 636 AN XY: 74438

Gnomad4 AFR AF: 0.0304

Gnomad4 AMR AF: 0.00216

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000735

Gnomad4 OTH AF: 0.00520

Alfa AF: 0.000946 Hom.: 0

Bravo AF: 0.00960

Asia WGS AF: 0.00289 AC: 10 AN: 3478

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Alzheimer disease Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 27, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.66
Cadd	Benign	12
Dann	Benign	0.88

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs45455403; hg19: chr21-27253391;