rs765443042

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PVS1_StrongPM2PP5

The NM_016277.5(RAB23):​c.82C>T​(p.Arg28Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000372 in 1,613,458 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000040 ( 0 hom. )

Consequence

RAB23
NM_016277.5 stop_gained

Scores

2
4
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:5U:1

Conservation

PhyloP100: 1.28
Variant links:
Genes affected
RAB23 (HGNC:14263): (RAB23, member RAS oncogene family) This gene encodes a small GTPase of the Ras superfamily. Rab proteins are involved in the regulation of diverse cellular functions associated with intracellular membrane trafficking, including autophagy and immune response to bacterial infection. The encoded protein may play a role in central nervous system development by antagonizing sonic hedgehog signaling. Disruption of this gene has been implicated in Carpenter syndrome as well as cancer. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2013]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.885 CDS is truncated, and there are 2 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 6-57210299-G-A is Pathogenic according to our data. Variant chr6-57210299-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 280858.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=1, Pathogenic=2}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
RAB23NM_016277.5 linkuse as main transcriptc.82C>T p.Arg28Ter stop_gained 2/7 ENST00000468148.6 NP_057361.3

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
RAB23ENST00000468148.6 linkuse as main transcriptc.82C>T p.Arg28Ter stop_gained 2/71 NM_016277.5 ENSP00000417610 P1
RAB23ENST00000317483.4 linkuse as main transcriptc.82C>T p.Arg28Ter stop_gained 2/71 ENSP00000320413 P1

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
AN:
152070
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000119
AC:
3
AN:
251340
Hom.:
0
AF XY:
0.0000147
AC XY:
2
AN XY:
135836
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000397
AC:
58
AN:
1461388
Hom.:
0
Cov.:
31
AF XY:
0.0000344
AC XY:
25
AN XY:
727016
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000486
Gnomad4 OTH exome
AF:
0.0000497
GnomAD4 genome
AF:
0.0000132
AC:
2
AN:
152070
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74260
show subpopulations
Gnomad4 AFR
AF:
0.0000242
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000282
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000247
AC:
3
EpiCase
AF:
0.0000545
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:5Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

RAB23-related Carpenter syndrome Pathogenic:2Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJun 20, 2017The RAB23 c.82C>T (p.Arg28Ter) stop-gained variant has been reported in one study and is found in two brothers with Carpenter syndrome with the p.Arg28Ter and p.Leu145Ter variants on a complex allele. These variants are on the maternal allele and are in trans with p.Leu145Ter on the paternal allele (Jenkins et al. 2011). The clinically unaffected mother was confirmed to be a carrier of the complex allele. Control data are unavailable for this variant, which is reported at a frequency of 0.000025 in the Total population in the Exome Aggregation Consortium. Due to the potential impact of stop-gained variants, the p.Arg28Ter variant is classified as a variant of unknown significance but suspicious for pathogenicity for Carpenter syndrome. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. -
Likely pathogenic, criteria provided, single submitterclinical testingGenetics and Molecular Pathology, SA PathologyMar 02, 2022- -
Pathogenic, no assertion criteria providedclinical testingNatera, Inc.Sep 16, 2020- -
RAB23-related disorder Pathogenic:1
Pathogenic, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesJan 17, 2024The RAB23 c.82C>T variant is predicted to result in premature protein termination (p.Arg28*). This variant has been reported in six individuals from three families with Carpenter syndrome (Jenkins et al. 2011. PubMed ID: 21412941; Ben-Salem et al. 2013. PubMed ID: 23599695; Lodhia et al. 2021. PubMed ID: 33368989). In two of those individuals from one family, the c.434T>A and c.82C>T variant were reported to be on the same allele (cis orientation) with a nonsense variant on the other allele (Jenkins et al. 2011. PubMed ID: 21412941). In another family, both parents were heterozygous for the c.82C>T variant and the child with Carpenter syndrome was homozygous for the c.82C>T variant (Lodhia et al. 2021. PubMed ID: 33368989). Chain-terminating variants in RAB23 are expected to be pathogenic. Taken together, this variant is interpreted as pathogenic. -
Carpenter syndrome Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpAug 31, 2023This sequence change creates a premature translational stop signal (p.Arg28*) in the RAB23 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in RAB23 are known to be pathogenic (PMID: 17503333, 21412941). This variant is present in population databases (rs765443042, gnomAD 0.007%). This premature translational stop signal has been observed in individual(s) with Carpenter syndrome, although in one family this variant was shown to be on the same chromosome (in cis) with another pathogenic variant (p.Leu145*) (PMID: 21412941, 23599695). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 280858). For these reasons, this variant has been classified as Pathogenic. -
not provided Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingGeneDxJun 06, 2023Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Reported previously in two siblings with Carpenter syndrome who harbored a maternally inherited R28X; L145X complex allele in trans with a paternally inherited L145X variant (Jenkins et al., 2011); This variant is associated with the following publications: (PMID: 23599695, 21412941, 33368989) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Pathogenic
0.58
CADD
Pathogenic
37
DANN
Uncertain
1.0
Eigen
Uncertain
0.47
Eigen_PC
Uncertain
0.27
FATHMM_MKL
Uncertain
0.88
D
MutationTaster
Benign
1.0
A;A
Vest4
0.82
GERP RS
2.7

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs765443042; hg19: chr6-57075097; API