Genetic Variant ALKBH2:p.Arg254Cys (chr12-109088232-G-A) – ACMG Classification: Likely_pathogenic (8 pts)

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1PM2PP3_Strong

The NM_001145374.2(ALKBH2):c.760C>T(p.Arg254Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000314 in 1,590,786 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000033 ( 0 hom. )

Consequence

ALKBH2
NM_001145374.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 3.76

Variant links:

Genes affected

ALKBH2 (HGNC:32487): (alkB homolog 2, alpha-ketoglutarate dependent dioxygenase) The Escherichia coli AlkB protein protects against the cytotoxicity of methylating agents by repair of the specific DNA lesions generated in single-stranded DNA. ALKBH2 and ALKBH3 (MIM 610603) are E. coli AlkB homologs that catalyze the removal of 1-methyladenine and 3-methylcytosine (Duncan et al., 2002 [PubMed 12486230]).[supplied by OMIM, Mar 2008]

ALKBH2 links:

USP30 (HGNC:20065): (ubiquitin specific peptidase 30) USP30, a member of the ubiquitin-specific protease family (see USP1, MIM 603478), is a novel mitochondrial deubiquitinating (DUB) enzyme (Nakamura and Hirose, 2008 [PubMed 18287522]).[supplied by OMIM, Dec 2008]

USP30 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

PM1

In a binding_site (size 0) in uniprot entity ALKB2_HUMAN

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.974

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ALKBH2	NM_001145374.2 link	c.760C>T	p.Arg254Cys	missense_variant	Exon 4 of 4	ENST00000429722.3	NP_001138846.1	Q6NS38-1
USP30	NM_032663.5 link	c.*2301G>A		downstream_gene_variant		ENST00000257548.10	NP_116052.2	Q70CQ3A0A024RBM3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ALKBH2	ENST00000429722.3 link	c.760C>T	p.Arg254Cys	missense_variant	Exon 4 of 4	5	NM_001145374.2	ENSP00000398181.1		Q6NS38-1
USP30	ENST00000257548.10 link	c.*2301G>A		downstream_gene_variant		1	NM_032663.5	ENSP00000257548.5		Q70CQ3

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152150

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.000288

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000593

AC:

AN:

236254

Hom.:

AF XY:

0.0000548

AC XY:

AN XY:

127678

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.000757

Gnomad EAS exome

AF:

0.000225

Gnomad SAS exome

AF:

0.0000367

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000183

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000327

AC:

AN:

1438636

Hom.:

Cov.:

AF XY:

0.0000225

AC XY:

AN XY:

712518

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000486

Gnomad4 ASJ exome

AF:

0.000785

Gnomad4 EAS exome

AF:

0.000102

Gnomad4 SAS exome

AF:

0.0000360

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000127

Gnomad4 OTH exome

AF:

0.0000505

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152150

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74334

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.000288

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000130

Hom.:

Bravo

AF:

0.0000416

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000116

AC:

ExAC

AF:

0.0000577

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Feb 12, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.760C>T (p.R254C) alteration is located in exon 4 (coding exon 3) of the ALKBH2 gene. This alteration results from a C to T substitution at nucleotide position 760, causing the arginine (R) at amino acid position 254 to be replaced by a cysteine (C). 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

Pathogenic

0.79

BayesDel_addAF

Uncertain

0.16

BayesDel_noAF

Pathogenic

0.29

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.42

T;T

Eigen

Uncertain

0.55

Eigen_PC

Uncertain

0.33

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Uncertain

0.90

.;D

M_CAP

Uncertain

0.13

MetaRNN

Pathogenic

0.97

D;D

MetaSVM

Uncertain

0.70

MutationAssessor

Pathogenic

3.9

H;H

PrimateAI

Benign

0.47

PROVEAN

Pathogenic

-6.8

D;D

REVEL

Pathogenic

0.78

Sift

Benign

0.030

D;D

Sift4G

Pathogenic

0.0

D;D

Polyphen

1.0

D;D

Vest4

0.96

MVP

0.86

MPC

0.72

ClinPred

0.98

GERP RS

3.7

Varity_R

0.94

gMVP

0.89

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

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