Genetic Variant TBC1D20:p.Arg67Gly (chr20-447946-G-C) – ACMG Classification: Uncertain_significance (0 pts)

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_144628.4(TBC1D20):c.199C>G(p.Arg67Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,798 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

Frequency

Genomes: not found (cov: 31)

Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

TBC1D20
NM_144628.4 missense

Scores

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: 1.07

Publications

0 publications found

Variant links:

Genes affected

TBC1D20 (HGNC:16133): (TBC1 domain family member 20) This gene encodes a protein that belongs to a family of GTPase activator proteins of Rab-like small GTPases. The encoded protein and its cognate GTPase, Rab1, bind the nonstructural protein 5A (NS5A) of the hepatitis C virus (HCV) to mediate viral replication. Depletion of this protein inhibits replication of the virus and HCV infection. Mutations in this gene are associated with Warburg micro syndrome 4. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Mar 2014]

TBC1D20 Gene-Disease associations (from GenCC):

Warburg micro syndrome 4
Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
Warburg micro syndrome
Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

TBC1D20 links:

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ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.24021223).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_144628.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TBC1D20	NM_144628.4	MANE Select	c.199C>G	p.Arg67Gly	missense	Exon 2 of 8	NP_653229.1
	TBC1D20	NR_111901.2		n.327C>G		non_coding_transcript_exon	Exon 2 of 10

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
TBC1D20	ENST00000354200.5	TSL:1 MANE Select	c.199C>G	p.Arg67Gly	missense	Exon 2 of 8	ENSP00000346139.4
TBC1D20	ENST00000461304.5	TSL:1	n.199C>G		non_coding_transcript_exon	Exon 2 of 10	ENSP00000432280.1
TBC1D20	ENST00000679895.1		c.199C>G	p.Arg67Gly	missense	Exon 2 of 9	ENSP00000505197.1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

AF:

0.00000205

AC:

AN:

1461798

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

727210

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33480

American (AMR)

AF:

0.00

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.00

AC:

AN:

86254

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53368

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5762

European-Non Finnish (NFE)

AF:

0.00000270

AC:

AN:

1111980

Other (OTH)

AF:

0.00

AC:

AN:

60394

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.492

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

Cov.:

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.17

BayesDel_addAF

Benign

-0.15

BayesDel_noAF

Benign

-0.45

CADD

Benign

(source)

DANN

Uncertain

0.99

DEOGEN2

Benign

0.23

Eigen

Benign

-0.56

Eigen_PC

Benign

-0.72

FATHMM_MKL

Benign

0.16

LIST_S2

Uncertain

0.96

M_CAP

Benign

0.012

MetaRNN

Benign

0.24

MetaSVM

Benign

-1.0

MutationAssessor

Uncertain

2.8

PhyloP100

1.1

PrimateAI

Benign

0.22

PROVEAN

Pathogenic

-4.8

REVEL

Benign

0.12

Sift

Benign

0.11

Sift4G

Benign

0.10

Polyphen

0.67

Vest4

0.36

MutPred

0.54

Loss of stability (P = 0.0143)

MVP

0.30

MPC

0.63

ClinPred

0.66

GERP RS

-0.34

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.40

gMVP

0.32

Mutation Taster

=89/11

polymorphism

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over