Genetic Variant KBTBD8:p.Ala340Val (chr3-67003986-C-T) – ACMG Classification: Uncertain_significance (3 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP3

The NM_032505.3(KBTBD8):c.1019C>T(p.Ala340Val) variant causes a missense change. The variant allele was found at a frequency of 0.00000124 in 1,613,952 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 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

KBTBD8
NM_032505.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 6.03

Variant links:

Genes affected

KBTBD8 (HGNC:30691): (kelch repeat and BTB domain containing 8) Involved in neural crest cell development; neural crest formation; and protein monoubiquitination. Part of Cul3-RING ubiquitin ligase complex. [provided by Alliance of Genome Resources, Apr 2022]

KBTBD8 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

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, 0.769

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KBTBD8	NM_032505.3 link	c.1019C>T	p.Ala340Val	missense_variant	Exon 3 of 4	ENST00000417314.2	NP_115894.2	Q8NFY9-1
KBTBD8	XM_005264771.4 link	c.788C>T	p.Ala263Val	missense_variant	Exon 2 of 3		XP_005264828.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	UniProt
KBTBD8	ENST00000417314.2 link	c.1019C>T	p.Ala340Val	missense_variant	Exon 3 of 4	2	NM_032505.3	ENSP00000401878.2	Q8NFY9-1
KBTBD8	ENST00000460576.5 link	c.17-3936C>T		intron_variant	Intron 1 of 1	2		ENSP00000419738.1	Q8NFY9-2
KBTBD8	ENST00000469661.1 link	n.*158C>T		downstream_gene_variant		5

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152142

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461810

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

727210

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000224

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:

0.00000657

AC:

AN:

152142

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74310

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000655

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

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

Feb 20, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1019C>T (p.A340V) alteration is located in exon 3 (coding exon 3) of the KBTBD8 gene. This alteration results from a C to T substitution at nucleotide position 1019, causing the alanine (A) at amino acid position 340 to be replaced by a valine (V). 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

0.69

BayesDel_addAF

Uncertain

0.16

BayesDel_noAF

Uncertain

-0.010

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Benign

0.40

Eigen

Uncertain

0.63

Eigen_PC

Uncertain

0.64

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Uncertain

0.92

M_CAP

Uncertain

0.12

MetaRNN

Pathogenic

0.77

MetaSVM

Uncertain

-0.077

MutationAssessor

Benign

2.0

PrimateAI

Pathogenic

0.89

PROVEAN

Uncertain

-2.8

REVEL

Uncertain

0.49

Sift

Pathogenic

0.0

Sift4G

Benign

0.26

Polyphen

0.92

Vest4

0.72

MutPred

0.49

Gain of glycosylation at Y338 (P = 0.0246);

MVP

0.83

MPC

0.91

ClinPred

0.96

GERP RS

5.3

Varity_R

0.69

gMVP

0.63

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