13-75286878-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_014832.5(TBC1D4):​c.3811G>A​(p.Ala1271Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000223 in 1,613,946 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 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: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

TBC1D4
NM_014832.5 missense

Scores

19

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.521
Variant links:
Genes affected
TBC1D4 (HGNC:19165): (TBC1 domain family member 4) This gene is a member of the Tre-2/BUB2/CDC16 domain family. The protein encoded by this gene is a Rab-GTPase-activating protein, and contains two phopshotyrosine-binding domains (PTB1 and PTB2), a calmodulin-binding domain (CBD), a Rab-GTPase domain, and multiple AKT phosphomotifs. This protein is thought to play an important role in glucose homeostasis by regulating the insulin-dependent trafficking of the glucose transporter 4 (GLUT4), important for removing glucose from the bloodstream into skeletal muscle and fat tissues. Reduced expression of this gene results in an increase in GLUT4 levels at the plasma membrane, suggesting that this protein is important in intracellular retention of GLUT4 under basal conditions. When exposed to insulin, this protein is phosphorylated, dissociates from GLUT4 vesicles, resulting in increased GLUT4 at the cell surface, and enhanced glucose transport. Phosphorylation of this protein by AKT is required for proper translocation of GLUT4 to the cell surface. Individuals homozygous for a mutation in this gene are at higher risk for type 2 diabetes and have higher levels of circulating glucose and insulin levels after glucose ingestion. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Aug 2015]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.04030195).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TBC1D4NM_014832.5 linkc.3811G>A p.Ala1271Thr missense_variant Exon 21 of 21 ENST00000377636.8 NP_055647.2 O60343-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TBC1D4ENST00000377636.8 linkc.3811G>A p.Ala1271Thr missense_variant Exon 21 of 21 2 NM_014832.5 ENSP00000366863.3 O60343-1
TBC1D4ENST00000431480.6 linkc.3787G>A p.Ala1263Thr missense_variant Exon 20 of 20 1 ENSP00000395986.2 O60343-3
TBC1D4ENST00000377625.6 linkc.3622G>A p.Ala1208Thr missense_variant Exon 19 of 19 1 ENSP00000366852.2 O60343-2
TBC1D4ENST00000648194.1 linkc.3079G>A p.Ala1027Thr missense_variant Exon 20 of 20 ENSP00000496983.1 A0A3B3IRT3

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152128
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000386
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
GnomAD3 exomes
AF:
0.0000441
AC:
11
AN:
249194
Hom.:
0
AF XY:
0.0000518
AC XY:
7
AN XY:
135204
show subpopulations
Gnomad AFR exome
AF:
0.0000646
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000556
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000226
AC:
33
AN:
1461700
Hom.:
0
Cov.:
32
AF XY:
0.0000206
AC XY:
15
AN XY:
727142
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.000655
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000450
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152246
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74454
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000387
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000378
ESP6500AA
AF:
0.000264
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000579
AC:
7
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not specified Uncertain:1
Dec 14, 2024
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The c.3811G>A (p.A1271T) alteration is located in exon 21 (coding exon 21) of the TBC1D4 gene. This alteration results from a G to A substitution at nucleotide position 3811, causing the alanine (A) at amino acid position 1271 to be replaced by a threonine (T). 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
0.070
BayesDel_addAF
Benign
-0.58
T
BayesDel_noAF
Benign
-0.71
CADD
Benign
8.5
DANN
Benign
0.27
DEOGEN2
Benign
0.026
.;.;.;T
Eigen
Benign
-0.59
Eigen_PC
Benign
-0.50
FATHMM_MKL
Benign
0.14
N
LIST_S2
Benign
0.72
T;T;T;T
M_CAP
Benign
0.0074
T
MetaRNN
Benign
0.040
T;T;T;T
MetaSVM
Benign
-0.88
T
MutationAssessor
Benign
1.4
.;.;.;L
PrimateAI
Benign
0.37
T
PROVEAN
Benign
-0.24
.;N;N;N
REVEL
Benign
0.054
Sift
Benign
0.26
.;T;T;T
Sift4G
Benign
0.63
.;T;T;T
Polyphen
0.14, 0.40, 0.15
.;B;B;B
Vest4
0.031, 0.030, 0.047
MVP
0.49
MPC
0.32
ClinPred
0.021
T
GERP RS
5.6
Varity_R
0.027
gMVP
0.21

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.

Other links and lift over

dbSNP: rs185278132; hg19: chr13-75861014; COSMIC: COSV66489725; API