Genetic Variant APEX2:p.Leu177Phe (chrX-55003070-G-T) – ACMG Classification: Likely_benign (-3 pts)

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 1P and 4B. PP3BS2

The NM_014481.4(APEX2):c.531G>T(p.Leu177Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000619 in 1,210,889 control chromosomes in the GnomAD database, including 1 homozygotes. There are 20 hemizygotes in GnomAD. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000018 ( 0 hom., 1 hem., cov: 23)

Exomes 𝑓: 0.000066 ( 1 hom. 19 hem. )

Consequence

APEX2
NM_014481.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.727

Variant links:

Genes affected

APEX2 (HGNC:17889): (apurinic/apyrimidinic endodeoxyribonuclease 2) Apurinic/apyrimidinic (AP) sites occur frequently in DNA molecules by spontaneous hydrolysis, by DNA damaging agents or by DNA glycosylases that remove specific abnormal bases. AP sites are pre-mutagenic lesions that can prevent normal DNA replication so the cell contains systems to identify and repair such sites. Class II AP endonucleases cleave the phosphodiester backbone 5' to the AP site. This gene encodes a protein shown to have a weak class II AP endonuclease activity. Most of the encoded protein is located in the nucleus but some is also present in mitochondria. This protein may play an important role in both nuclear and mitochondrial base excision repair. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Nov 2012]

APEX2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.763

BS2

High Hemizygotes in GnomAdExome4 at 19 gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
APEX2	NM_014481.4 link	c.531G>T	p.Leu177Phe	missense_variant	Exon 4 of 6	ENST00000374987.4	NP_055296.2	Q9UBZ4E5KN95
APEX2	NM_001271748.2 link	c.18G>T	p.Leu6Phe	missense_variant	Exon 3 of 5		NP_001258677.1	B7ZA71B4DWI9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
APEX2	ENST00000374987.4 link	c.531G>T	p.Leu177Phe	missense_variant	Exon 4 of 6	1	NM_014481.4	ENSP00000364126.3		Q9UBZ4
APEX2	ENST00000471758.1 link	n.380G>T		non_coding_transcript_exon_variant	Exon 3 of 5	2

Frequencies

GnomAD3 genomes

AF:

0.0000177

AC:

AN:

112788

Hom.:

Cov.:

AF XY:

0.0000286

AC XY:

AN XY:

34932

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000375

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000219

AC:

AN:

182806

Hom.:

AF XY:

0.0000297

AC XY:

AN XY:

67286

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000490

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000665

AC:

AN:

1098101

Hom.:

Cov.:

AF XY:

0.0000523

AC XY:

AN XY:

363461

show subpopulations

Gnomad4 AFR exome

AF:

0.00

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:

0.0000796

Gnomad4 OTH exome

AF:

0.000130

GnomAD4 genome

AF:

0.0000177

AC:

AN:

112788

Hom.:

Cov.:

AF XY:

0.0000286

AC XY:

AN XY:

34932

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000375

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000416

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000297

AC:

ExAC

AF:

0.00000824

AC:

EpiCase

AF:

0.000109

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Aug 28, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.531G>T (p.L177F) alteration is located in exon 4 (coding exon 4) of the APEX2 gene. This alteration results from a G to T substitution at nucleotide position 531, causing the leucine (L) at amino acid position 177 to be replaced by a phenylalanine (F). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.50

BayesDel_addAF

Benign

-0.070

BayesDel_noAF

Benign

-0.16

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.60

FATHMM_MKL

Benign

0.67

LIST_S2

Uncertain

0.91

M_CAP

Pathogenic

0.74

MetaRNN

Pathogenic

0.76

MetaSVM

Uncertain

-0.084

MutationAssessor

Benign

2.0

PrimateAI

Uncertain

0.67

PROVEAN

Uncertain

-3.3

REVEL

Uncertain

0.56

Sift

Uncertain

0.0060

Sift4G

Uncertain

0.0070

Polyphen

1.0

Vest4

0.49

MutPred

0.62

Loss of stability (P = 0.0506);

MVP

0.82

MPC

0.64

ClinPred

0.66

GERP RS

1.6

Varity_R

0.54

gMVP

0.84

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over