X-106820880-C-A

Position:

chrX-106820880-C-A

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_017752.3(TBC1D8B):c.245C>A(p.Ala82Asp) variant causes a missense change. The variant allele was found at a frequency of 0.00000688 in 1,163,343 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 4 hemizygotes in GnomAD. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000018 ( 0 hom., 1 hem., cov: 23)

Exomes 𝑓: 0.0000057 ( 0 hom. 3 hem. )

Consequence

TBC1D8B
NM_017752.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 4.00

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 -6 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.09587476).

BS2

High Hemizygotes in GnomAdExome4 at 3 XL gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TBC1D8B	NM_017752.3 linkuse as main transcript	c.245C>A	p.Ala82Asp	missense_variant	3/21	ENST00000357242.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TBC1D8B	ENST00000357242.10 linkuse as main transcript	c.245C>A	p.Ala82Asp	missense_variant	3/21	1	NM_017752.3	P2	Q0IIM8-1

Frequencies

GnomAD3 genomes

AF:

0.0000180

AC:

AN:

111183

Hom.:

Cov.:

AF XY:

0.0000298

AC XY:

AN XY:

33591

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:

0.000751

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.00000570

AC:

AN:

1052108

Hom.:

Cov.:

AF XY:

0.00000908

AC XY:

AN XY:

330218

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:

0.000126

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000180

AC:

AN:

111235

Hom.:

Cov.:

AF XY:

0.0000297

AC XY:

AN XY:

33653

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:

0.000754

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Nephrotic syndrome, type 20

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Neuberg Centre For Genomic Medicine, NCGM

The missense variant c.245C>A (p.Ala82Asp) in TBC1D8B gene has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. The p.Ala82Asp variant is novel (not in any individuals) in gnomAD Exomes and 1000 Genomes. The amino acid Ala at position 82 is changed to a Asp changing protein sequence and it might alter its composition and physico-chemical properties. The variant is predicted to be damaging by both SIFT and PolyPhen2. The residue is conserved across species. The amino acid change p.Ala82Asp in TBC1D8B is predicted as conserved by GERP++ and PhyloP across 100 vertebrates. For these reasons, this variant has been classified as Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.54

BayesDel_addAF

Benign

-0.084

BayesDel_noAF

Benign

-0.36

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Benign

0.082

T;.;T;T

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Benign

0.68

T;T;T;T

M_CAP

Benign

0.048

MetaRNN

Benign

0.096

T;T;T;T

MetaSVM

Benign

-1.1

MutationAssessor

Uncertain

2.1

M;M;.;.

MutationTaster

Benign

1.0

D;D;D;D

PrimateAI

Uncertain

0.57

PROVEAN

Benign

-2.2

N;D;D;N

REVEL

Benign

0.17

Sift

Benign

0.050

D;T;T;T

Sift4G

Benign

0.14

T;T;D;T

Polyphen

1.0

D;.;D;.

Vest4

0.23

MutPred

0.36

Gain of solvent accessibility (P = 0.0202);Gain of solvent accessibility (P = 0.0202);Gain of solvent accessibility (P = 0.0202);Gain of solvent accessibility (P = 0.0202);

MVP

0.26

MPC

0.34

ClinPred

0.72

GERP RS

5.1

Varity_R

0.61

gMVP

0.66

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.030

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