6-41061455-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_006789.4(APOBEC2):c.259C>T(p.Arg87Trp) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,292 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: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: APOBEC2 NM_006789.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.72

Genes affected

APOBEC2 (HGNC:605): (apolipoprotein B mRNA editing enzyme catalytic subunit 2) Enables cytidine deaminase activity and identical protein binding activity. Involved in DNA demethylation. Acts upstream of or within cytidine to uridine editing. Predicted to be active in cytoplasm and nucleus. [provided by Alliance of Genome Resources, Apr 2022]

OARD1 (HGNC:21257): (O-acyl-ADP-ribose deacylase 1) The protein encoded by this gene is a deacylase that can convert O-acetyl-ADP-ribose to ADP-ribose and acetate, O-propionyl-ADP-ribose to ADP-ribose and propionate, and O-butyryl-ADP-ribose to ADP-ribose and butyrate. The ADP-ribose product is able to inhibit these reactions through a competitive feedback loop. [provided by RefSeq, Jul 2016]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.786

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
APOBEC2	NM_006789.4	c.259C>T	p.Arg87Trp	missense_variant	2/3	ENST00000244669.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
APOBEC2	ENST00000244669.3	c.259C>T	p.Arg87Trp	missense_variant	2/3	1	NM_006789.4	P1
OARD1	ENST00000482853.5	c.145+8621G>A		intron_variant, NMD_transcript_variant		2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461292 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 726936

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 03, 2022

The c.259C>T (p.R87W) alteration is located in exon 2 (coding exon 2) of the APOBEC2 gene. This alteration results from a C to T substitution at nucleotide position 259, causing the arginine (R) at amino acid position 87 to be replaced by a tryptophan (W). 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	Benign	0.27
BayesDel_addAF	Uncertain	0.042	T
BayesDel_noAF	Benign	-0.18
Cadd	Uncertain	25
Dann	Pathogenic	1.0
DEOGEN2	Benign	0.20	T
Eigen	Uncertain	0.29
Eigen_PC	Uncertain	0.23
FATHMM_MKL	Uncertain	0.85	D
LIST_S2	Uncertain	0.86	D
M_CAP	Benign	0.046	D
MetaRNN	Pathogenic	0.79	D
MetaSVM	Benign	-0.74	T
MutationAssessor	Uncertain	2.3	M
MutationTaster	Benign	0.98	N
PrimateAI	Benign	0.45	T
PROVEAN	Uncertain	-3.6	D
REVEL	Uncertain	0.45
Sift	Uncertain	0.012	D
Sift4G	Uncertain	0.0020	D
Polyphen		1.0	D
Vest4		0.65
MutPred		0.69		Loss of disorder (P = 0.0095);
MVP		0.84
MPC		0.30
ClinPred		0.98	D
GERP RS		3.9
Varity_R		0.65
gMVP		0.79

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: rs1581991093; hg19: chr6-41029194;