rs724159975

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_020461.4(TUBGCP6):​c.2215C>T​(p.Arg739*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,613,916 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 Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000041 ( 0 hom. )

Consequence

TUBGCP6
NM_020461.4 stop_gained

Scores

4
4
6

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 2.49

Publications

2 publications found
Variant links:
Genes affected
TUBGCP6 (HGNC:18127): (tubulin gamma complex component 6) The protein encoded by this gene is part of a large multisubunit complex required for microtubule nucleation at the centrosome. [provided by RefSeq, Jul 2008]
TUBGCP6 Gene-Disease associations (from GenCC):
  • microcephaly and chorioretinopathy 1
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, G2P, ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 22-50224196-G-A is Pathogenic according to our data. Variant chr22-50224196-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 162403.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TUBGCP6NM_020461.4 linkc.2215C>T p.Arg739* stop_gained Exon 13 of 25 ENST00000248846.10 NP_065194.3
TUBGCP6XR_001755343.3 linkn.2779C>T non_coding_transcript_exon_variant Exon 13 of 20
TUBGCP6XR_007067982.1 linkn.2779C>T non_coding_transcript_exon_variant Exon 13 of 19
TUBGCP6XR_938347.3 linkn.2779C>T non_coding_transcript_exon_variant Exon 13 of 23

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TUBGCP6ENST00000248846.10 linkc.2215C>T p.Arg739* stop_gained Exon 13 of 25 1 NM_020461.4 ENSP00000248846.5

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152118
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000410
AC:
6
AN:
1461798
Hom.:
0
Cov.:
31
AF XY:
0.00000550
AC XY:
4
AN XY:
727204
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53340
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1112008
Other (OTH)
AF:
0.00
AC:
0
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000131
AC:
2
AN:
152118
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74306
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41414
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10596
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:2
Jan 10, 2023
GeneDx
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Identified with a second TUBGCP6 variant in a patient with microcephaly with simplified gyral pattern, retinal dystrophy, congenital heart defects, and triphalangeal thumbs in published literature (Martin et al., 2014); Nonsense 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; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 25344692, 34426522, Chen2022[CaseReport])

May 28, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Arg739*) in the TUBGCP6 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in TUBGCP6 are known to be pathogenic (PMID: 25344692). This variant is present in population databases (rs724159975, gnomAD 0.007%). This premature translational stop signal has been observed in individual(s) with microcephalic primordial dwarfism and centriole dysfunction (PMID: 25344692). ClinVar contains an entry for this variant (Variation ID: 162403). For these reasons, this variant has been classified as Pathogenic.

Microcephaly and chorioretinopathy 1 Pathogenic:1
Dec 01, 2014
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.63
D
BayesDel_noAF
Pathogenic
0.58
CADD
Pathogenic
38
DANN
Uncertain
1.0
DEOGEN2
Benign
0.0
.;.
Eigen
Uncertain
0.63
Eigen_PC
Uncertain
0.48
FATHMM_MKL
Uncertain
0.87
D
LIST_S2
Benign
0.0
.;.
MetaRNN
Benign
0.0
.;.
MutationAssessor
Benign
0.0
.;.
PhyloP100
2.5
PROVEAN
Benign
0.0
.;.
REVEL
Benign
0.0
Sift
Pathogenic
0.0
.;.
Sift4G
Pathogenic
0.0
.;.
Vest4
0.19
GERP RS
4.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Mutation Taster
=0/200
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: rs724159975; hg19: chr22-50662625; COSMIC: COSV50548883; COSMIC: COSV50548883; API