2-101022316-T-G

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BP4_Strong

The NM_001330348.2(TBC1D8):c.2726A>C(p.Gln909Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000209 in 1,612,648 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.00024 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00021 ( 2 hom. )

Consequence

TBC1D8
NM_001330348.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.00900

Variant links:

Genes affected

TBC1D8 (HGNC:17791): (TBC1 domain family member 8) Predicted to enable GTPase activator activity. Predicted to be involved in activation of GTPase activity and intracellular protein transport. Predicted to be located in membrane. [provided by Alliance of Genome Resources, Apr 2022]

TBC1D8 links:

RPL31 (HGNC:10334): (ribosomal protein L31) Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes a ribosomal protein that is a component of the 60S subunit. The protein belongs to the L31E family of ribosomal proteins. It is located in the cytoplasm. Higher levels of expression of this gene in familial adenomatous polyps compared to matched normal tissues have been observed. As is typical for genes encoding ribosomal proteins, there are multiple processed pseudogenes of this gene dispersed through the genome. Alternatively spliced transcript variants encoding distinct isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

RPL31 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.06395319).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
TBC1D8	NM_001330348.2 linkuse as main transcript	c.2726A>C	p.Gln909Pro	missense_variant	16/20	ENST00000409318.2
TBC1D8	NM_001102426.3 linkuse as main transcript	c.2681A>C	p.Gln894Pro	missense_variant	16/20
TBC1D8	NR_138475.2 linkuse as main transcript	n.2692A>C		non_coding_transcript_exon_variant	15/19

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TBC1D8	ENST00000409318.2 linkuse as main transcript	c.2726A>C	p.Gln909Pro	missense_variant	16/20	5	NM_001330348.2	A1
TBC1D8	ENST00000376840.8 linkuse as main transcript	c.2681A>C	p.Gln894Pro	missense_variant	16/20	1		P4	O95759-1
RPL31	ENST00000441435.1 linkuse as main transcript	c.310-1309T>G		intron_variant		2
TBC1D8	ENST00000494011.1 linkuse as main transcript	n.58A>C		non_coding_transcript_exon_variant	1/3	2

Frequencies

GnomAD3 genomes

AF:

0.000236

AC:

AN:

152244

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.000288

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000514

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000377

AC:

AN:

246660

Hom.:

AF XY:

0.000403

AC XY:

AN XY:

134008

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.000702

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.000140

Gnomad NFE exome

AF:

0.000742

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000206

AC:

301

AN:

1460404

Hom.:

Cov.:

AF XY:

0.000224

AC XY:

163

AN XY:

726538

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.000460

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.000318

Gnomad4 NFE exome

AF:

0.000228

Gnomad4 OTH exome

AF:

0.000315

GnomAD4 genome

AF:

0.000236

AC:

AN:

152244

Hom.:

Cov.:

AF XY:

0.000229

AC XY:

AN XY:

74376

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.000288

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000514

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000382

Hom.:

Bravo

AF:

0.000144

ExAC

AF:

0.000562

AC:

EpiCase

AF:

0.000273

EpiControl

AF:

0.0000594

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 26, 2022

The c.2681A>C (p.Q894P) alteration is located in exon 16 (coding exon 16) of the TBC1D8 gene. This alteration results from a A to C substitution at nucleotide position 2681, causing the glutamine (Q) at amino acid position 894 to be replaced by a proline (P). 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

0.13

BayesDel_addAF

Benign

-0.39

BayesDel_noAF

Benign

-0.39

Cadd

Benign

Dann

Benign

0.96

DEOGEN2

Benign

0.046

T;.

Eigen

Benign

-0.69

Eigen_PC

Benign

-0.58

FATHMM_MKL

Benign

0.28

LIST_S2

Uncertain

0.94

D;D

M_CAP

Benign

0.028

MetaRNN

Benign

0.064

T;T

MetaSVM

Benign

-1.0

MutationAssessor

Benign

0.69

N;.

MutationTaster

Benign

0.96

N;N

PrimateAI

Benign

0.27

PROVEAN

Benign

-1.5

N;N

REVEL

Benign

0.12

Sift

Benign

0.068

T;T

Sift4G

Uncertain

0.043

D;D

Polyphen

0.049

B;.

Vest4

0.39

MutPred

0.59

Loss of ubiquitination at K899 (P = 0.1166);.;

MVP

0.44

MPC

0.32

ClinPred

0.030

GERP RS

4.0

Varity_R

0.25

gMVP

0.75

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