rs747538224

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 10P and 1B. PM1PP5_Very_StrongBP4

The NM_001199107.2(TBC1D24):​c.845C>G​(p.Pro282Arg) variant causes a missense change. The variant allele was found at a frequency of 0.0000328 in 1,613,882 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P282S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000034 ( 0 hom. )

Consequence

TBC1D24
NM_001199107.2 missense

Scores

2
10
7

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6U:2

Conservation

PhyloP100: 4.05

Publications

3 publications found
Variant links:
Genes affected
TBC1D24 (HGNC:29203): (TBC1 domain family member 24) This gene encodes a protein with a conserved domain, referred to as the TBC domain, characteristic of proteins which interact with GTPases. TBC domain proteins may serve as GTPase-activating proteins for a particular group of GTPases, the Rab (Ras-related proteins in brain) small GTPases which are involved in the regulation of membrane trafficking. Mutations in this gene are associated with familial infantile myoclonic epilepsy. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2011]
TBC1D24 Gene-Disease associations (from GenCC):
  • DOORS syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen, Orphanet, PanelApp Australia, G2P
  • familial infantile myoclonic epilepsy
    Inheritance: AR Classification: DEFINITIVE, MODERATE, SUPPORTIVE Submitted by: G2P, Ambry Genetics, Orphanet
  • autosomal dominant nonsyndromic hearing loss 65
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • autosomal dominant nonsyndromic hearing loss
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • malignant migrating partial seizures of infancy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • focal epilepsy-intellectual disability-cerebro-cerebellar malformation
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • hearing loss, autosomal recessive
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • progressive myoclonic epilepsy with dystonia
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • nonsyndromic genetic hearing loss
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen
  • autosomal recessive nonsyndromic hearing loss 86
    Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 9 uncertain in NM_001199107.2
PP5
Variant 16-2496993-C-G is Pathogenic according to our data. Variant chr16-2496993-C-G is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 207505.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP4
Computational evidence support a benign effect (MetaRNN=0.1366477). . Strength limited to SUPPORTING due to the PP5.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TBC1D24NM_001199107.2 linkc.845C>G p.Pro282Arg missense_variant Exon 2 of 8 ENST00000646147.1 NP_001186036.1 Q9ULP9-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TBC1D24ENST00000646147.1 linkc.845C>G p.Pro282Arg missense_variant Exon 2 of 8 NM_001199107.2 ENSP00000494678.1 Q9ULP9-1
ENSG00000260272ENST00000564543.1 linkc.845C>G p.Pro282Arg missense_variant Exon 1 of 3 2 ENSP00000455547.1 H3BQ06

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152276
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000196
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
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
GnomAD2 exomes
AF:
0.000176
AC:
44
AN:
249376
AF XY:
0.000118
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00125
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000165
GnomAD4 exome
AF:
0.0000342
AC:
50
AN:
1461606
Hom.:
0
Cov.:
31
AF XY:
0.0000275
AC XY:
20
AN XY:
727134
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00110
AC:
49
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53138
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112010
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.457
Heterozygous variant carriers
0
5
10
14
19
24
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<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
AF:
0.0000197
AC:
3
AN:
152276
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74398
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41478
American (AMR)
AF:
0.000196
AC:
3
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5206
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68050
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000868
Hom.:
0
Bravo
AF:
0.0000869
ExAC
AF:
0.000173
AC:
21

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:6Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:3
Feb 10, 2025
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Reported previously in individuals with clinical features consistent with TBC1D24-related DOORS spectrum disorder who also harbored a second TBC1D24 variant (PMID: 27502353, 27281533); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 27281533, 31440721, 29100083, 33281559, 27502353, 34926809) -

Mar 02, 2020
Clinical Genomics Laboratory, Stanford Medicine
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

The p.Pro282Arg variant in the TBC1D24 gene has been previously reported in at least 17 unrelated individuals with seizures and developmental delay, and co-segregated with disease in at least 3 affected relatives from 3 families (Appavu et al., 2016; GeneDx, personal communication, March 2, 2020; Hamdan et al., 2017; Invitae, personal communication, February 12, 2020). All affected individuals were homozygous or compound heterozygous. This variant was determined to be in trans with at least 4 different likely pathogenic or pathogenic variants consistent with autosomal recessive inheritance (GeneDx, personal communication, March 2, 2020; Hamdan et al., 2017; Invitae, personal communication, February 12, 2020). The presence of this variant with a diseaseassociated variant on the opposite allele increases suspicion for its pathogenicity. The p.Pro282Arg variant has also been identified in 45/35,374 Latino chromosomes by the Genome Aggregation Database (http://gnomad.broadinstitute.org/). Computational tools predict that this variant is deleterious; however, the accuracy of in silico algorithms is limited. These data were assessed using the ACMG/AMP variant interpretation guidelines. In summary, there is sufficient evidence to classify the p.Pro282Arg variant as pathogenic for autosomal recessive TBC1D24-associated disorders based on the information above. [ACMG evidence codes used: PM2; PM3_verystrong; PP1_moderate; PP3] -

May 12, 2023
Revvity Omics, Revvity
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Pathogenic:1
Jul 13, 2021
Ambry Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.845C>G (p.P282R) alteration is located in exon 2 (coding exon 1) of the TBC1D24 gene. This alteration results from a C to G substitution at nucleotide position 845, causing the proline (P) at amino acid position 282 to be replaced by an arginine (R). Based on data from the Genome Aggregation Database (gnomAD), the TBC1D24 c.845C>G alteration was observed in 0.02% (46/280780) of total alleles studied, with a frequency of 0.13% (45/35374) in the Latino subpopulation. This variant has been reported in the compound heterozygous state in three individuals with epilepsy (Appavu, 2016; Balestrini, 2016; Hamdan, 2017). The in silico prediction for the p.P282R alteration is inconclusive. Based on the available evidence, this alteration is classified as likely pathogenic. -

DOORS syndrome Pathogenic:1
Oct 22, 2019
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was determined to be pathogenic according to ACMG Guidelines, 2015 [PMID:25741868]. -

Developmental and epileptic encephalopathy, 1;C3892048:Autosomal dominant nonsyndromic hearing loss 65;CN236805:Caused by mutation in the TBC1 domain family, member 24 Pathogenic:1
Dec 02, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces proline, which is neutral and non-polar, with arginine, which is basic and polar, at codon 282 of the TBC1D24 protein (p.Pro282Arg). This variant is present in population databases (rs747538224, gnomAD 0.1%). This missense change has been observed in individual(s) with autosomal recessive epileptic encephalopathy (PMID: 27502353, 29100083; internal data). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 207505). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on TBC1D24 protein function. For these reasons, this variant has been classified as Pathogenic. -

developmental delay with seizures Uncertain:1
Aug 15, 2016
Clinical Molecular Genetics Laboratory, Johns Hopkins All Children's Hospital
Significance:Uncertain significance
Review Status:flagged submission
Collection Method:clinical testing

- -

not specified Uncertain:1
Aug 08, 2014
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:flagged submission
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.46
BayesDel_addAF
Benign
-0.087
T
BayesDel_noAF
Uncertain
0.060
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Benign
0.081
.;T;T;.;.;.;.
Eigen
Uncertain
0.54
Eigen_PC
Uncertain
0.45
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.95
.;.;D;D;D;D;D
M_CAP
Benign
0.065
D
MetaRNN
Benign
0.14
T;T;T;T;T;T;T
MetaSVM
Benign
-0.90
T
MutationAssessor
Uncertain
2.6
M;M;M;.;.;M;.
PhyloP100
4.0
PrimateAI
Uncertain
0.64
T
PROVEAN
Pathogenic
-5.3
D;.;D;.;.;.;D
REVEL
Uncertain
0.29
Sift
Uncertain
0.018
D;.;D;.;.;.;D
Sift4G
Benign
0.070
T;.;T;.;.;T;T
Polyphen
0.99
D;D;D;.;.;D;.
Vest4
0.88
MutPred
0.46
Gain of MoRF binding (P = 0.0015);Gain of MoRF binding (P = 0.0015);Gain of MoRF binding (P = 0.0015);Gain of MoRF binding (P = 0.0015);Gain of MoRF binding (P = 0.0015);Gain of MoRF binding (P = 0.0015);Gain of MoRF binding (P = 0.0015);
MVP
0.74
MPC
0.99, 1.4
ClinPred
0.27
T
GERP RS
5.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.58
gMVP
0.80
Mutation Taster
=4/96
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs747538224; hg19: chr16-2546994; API