Genetic Variant NAT8B:p.Arg136Gln (chr2-73700899-C-T) – ACMG Classification: Likely_benign (-4 pts)

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 2P and 6B. PM2BP4_StrongBP6_Moderate

The ENST00000377712.3(NAT8B):c.407G>A(p.Arg136Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000088 in 1,614,054 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 5/5 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000093 ( 0 hom. )

Consequence

NAT8B
ENST00000377712.3 missense

Scores

Clinical Significance

Likely benign criteria provided, single submitter B:1

Conservation

PhyloP100: 0.186

Variant links:

Genes affected

NAT8B (HGNC:30235): (N-acetyltransferase 8B (putative, gene/pseudogene)) This gene is highly similar to the N-acetyltransferase 8 (NAT8) gene which encodes a kidney and liver protein with homology to bacterial acetyltransferases involved in drug resistance. This gene is localized on chromosome 2 in the vicinity of the NAT8 gene and represents a human-specific transcribed pseudogene of NAT8. This gene contains two common polymorphic nonsense mutations that disrupt the active site of the protein. In the extremely rare event when both nonsense mutations are absent, the predicted protein would contain a complete acetyltransferase domain and would be identical in length to NAT8. [provided by RefSeq, Apr 2022]

NAT8B links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.84).

BP6

Variant 2-73700899-C-T is Benign according to our data. Variant chr2-73700899-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 3176550.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NAT8B	NR_132338.2 link	n.614G>A		non_coding_transcript_exon_variant	Exon 2 of 2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NAT8B	ENST00000377712.3 link	c.407G>A	p.Arg136Gln	missense_variant	Exon 1 of 1	6		ENSP00000485054.2

Frequencies

GnomAD3 genomes

AF:

0.0000394

AC:

AN:

152160

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000193

Gnomad SAS

AF:

0.000415

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000557

AC:

AN:

251426

Hom.:

AF XY:

0.0000736

AC XY:

AN XY:

135892

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.000294

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000352

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000930

AC:

136

AN:

1461894

Hom.:

Cov.:

106

AF XY:

0.000100

AC XY:

AN XY:

727248

show subpopulations

Gnomad4 AFR exome

AF:

0.000209

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.000359

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000737

Gnomad4 OTH exome

AF:

0.000265

GnomAD4 genome

AF:

0.0000394

AC:

AN:

152160

Hom.:

Cov.:

AF XY:

0.0000673

AC XY:

AN XY:

74316

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000193

Gnomad4 SAS

AF:

0.000415

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000450

Hom.:

Bravo

AF:

0.0000264

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Benign:1

Mar 14, 2023

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.84

CADD

Benign

1.5

DANN

Benign

0.71

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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