NM_017752.3:c.163G>A

Variant names:

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PP3_ModerateBS2

The NM_017752.3(TBC1D8B):c.163G>A(p.Asp55Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000821 in 1,205,973 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 35 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 0.000054 ( 0 hom., 2 hem., cov: 22)

Exomes 𝑓: 0.000085 ( 0 hom. 33 hem. )

Consequence

TBC1D8B
NM_017752.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 9.60

Variant links:

Genes affected

TBC1D8B (HGNC:24715): (TBC1 domain family member 8B) This gene encodes a protein with a TBC (Tre-2/Bub2/CDC16) domain. Some mammalian proteins with this domain have been shown to function as Rab-GAPs by binding to specific Rab proteins and affecting their GTPase activity. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2011]

TBC1D8B links:

MORC4 (HGNC:23485): (MORC family CW-type zinc finger 4) In human, the four current members of the microrchidia (morc) gene family share an N-terminal ATPase-like ATP-binding region and a CW four-cysteine zinc-finger motif. The protein encoded by this gene also has a nuclear matrix binding domain and a two-stranded coiled-coil motif near its C-terminus. This gene is widely expressed at low levels in normal tissues and has elevated expression in placenta and testis. Alternative splicing results in multiple transcript variants encoding distinct proteins. [provided by RefSeq, Jan 2010]

MORC4 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.843

BS2

High Hemizygotes in GnomAd4 at 2 XL gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TBC1D8B	NM_017752.3 link	c.163G>A	p.Asp55Asn	missense_variant	Exon 2 of 21	ENST00000357242.10	NP_060222.2	Q0IIM8-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TBC1D8B	ENST00000357242.10 link	c.163G>A	p.Asp55Asn	missense_variant	Exon 2 of 21	1	NM_017752.3	ENSP00000349781.5		Q0IIM8-1

Frequencies

GnomAD3 genomes

AF:

0.0000542

AC:

AN:

110741

Hom.:

Cov.:

AF XY:

0.0000604

AC XY:

AN XY:

33111

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:

0.000169

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000948

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000222

AC:

AN:

180437

Hom.:

AF XY:

0.0000612

AC XY:

AN XY:

65337

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:

0.0000495

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000849

AC:

AN:

1095232

Hom.:

Cov.:

AF XY:

0.0000913

AC XY:

AN XY:

361444

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:

0.000104

Gnomad4 OTH exome

AF:

0.000131

GnomAD4 genome

AF:

0.0000542

AC:

AN:

110741

Hom.:

Cov.:

AF XY:

0.0000604

AC XY:

AN XY:

33111

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:

0.000169

Gnomad4 NFE

AF:

0.0000948

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000529

TwinsUK

AF:

0.00

AC:

ALSPAC

AF:

0.000692

AC:

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000297

AC:

ExAC

AF:

0.0000494

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Nephrotic syndrome, type 20

Uncertain:2

Mar 04, 2021

Revvity Omics, Revvity

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Dec 01, 2023

Department of Pathology and Laboratory Medicine, Sinai Health System

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: research

- -

not specified

Uncertain:1

Dec 22, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.163G>A (p.D55N) alteration is located in exon 2 (coding exon 2) of the TBC1D8B gene. This alteration results from a G to A substitution at nucleotide position 163, causing the aspartic acid (D) at amino acid position 55 to be replaced by an asparagine (N). 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

0.89

BayesDel_addAF

Benign

-0.33

BayesDel_noAF

Benign

-0.53

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Benign

0.33

T;.;T;T

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Pathogenic

1.0

D;D;D;D

M_CAP

Pathogenic

0.72

MetaRNN

Pathogenic

0.84

D;D;D;D

MetaSVM

Benign

-0.96

MutationAssessor

Uncertain

2.7

M;M;.;.

PrimateAI

Pathogenic

0.80

PROVEAN

Uncertain

-3.8

D;D;D;D

REVEL

Uncertain

0.34

Sift

Uncertain

0.0010

D;T;D;D

Sift4G

Uncertain

0.0030

D;D;D;D

Polyphen

1.0

D;.;D;.

Vest4

0.76

MVP

0.40

MPC

0.45

ClinPred

0.78

GERP RS

5.8

Varity_R

0.79

gMVP

0.74

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