rs151102020

Variant summary

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

The NM_018943.3(TUBA8):​c.967G>A​(p.Val323Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000322 in 1,613,272 control chromosomes in the GnomAD database, including 1 homozygotes. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V323L) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00032 ( 0 hom., cov: 31)
Exomes 𝑓: 0.00032 ( 1 hom. )

Consequence

TUBA8
NM_018943.3 missense

Scores

8
9
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:7

Conservation

PhyloP100: 10.0

Publications

3 publications found
Variant links:
Genes affected
TUBA8 (HGNC:12410): (tubulin alpha 8) This gene encodes a member of the alpha tubulin protein family. Alpha tubulins are one of two core protein families (alpha and beta tubulins) that heterodimerize and assemble to form microtubules. Mutations in this gene are associated with polymicrogyria and optic nerve hypoplasia. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Jul 2010]
TUBA8 Gene-Disease associations (from GenCC):
  • polymicrogyria with optic nerve hypoplasia
    Inheritance: Unknown, AR Classification: SUPPORTIVE, LIMITED, NO_KNOWN Submitted by: Labcorp Genetics (formerly Invitae), G2P, Orphanet, ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TUBA8NM_018943.3 linkc.967G>A p.Val323Met missense_variant Exon 4 of 5 ENST00000330423.8 NP_061816.1
TUBA8NM_001193414.2 linkc.769G>A p.Val257Met missense_variant Exon 4 of 5 NP_001180343.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TUBA8ENST00000330423.8 linkc.967G>A p.Val323Met missense_variant Exon 4 of 5 1 NM_018943.3 ENSP00000333326.3
ENSG00000288683ENST00000474897.6 linkn.*857G>A non_coding_transcript_exon_variant Exon 8 of 9 5 ENSP00000434235.2
ENSG00000288683ENST00000474897.6 linkn.*857G>A 3_prime_UTR_variant Exon 8 of 9 5 ENSP00000434235.2

Frequencies

GnomAD3 genomes
AF:
0.000316
AC:
48
AN:
152072
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.000145
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000393
Gnomad ASJ
AF:
0.000864
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000470
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.000327
AC:
82
AN:
250692
AF XY:
0.000399
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000290
Gnomad ASJ exome
AF:
0.000300
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000565
Gnomad OTH exome
AF:
0.000164
GnomAD4 exome
AF:
0.000322
AC:
471
AN:
1461082
Hom.:
1
Cov.:
31
AF XY:
0.000333
AC XY:
242
AN XY:
726758
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33464
American (AMR)
AF:
0.000336
AC:
15
AN:
44672
Ashkenazi Jewish (ASJ)
AF:
0.000384
AC:
10
AN:
26064
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39684
South Asian (SAS)
AF:
0.000116
AC:
10
AN:
86166
European-Finnish (FIN)
AF:
0.0000375
AC:
2
AN:
53404
Middle Eastern (MID)
AF:
0.00139
AC:
8
AN:
5766
European-Non Finnish (NFE)
AF:
0.000350
AC:
389
AN:
1111528
Other (OTH)
AF:
0.000613
AC:
37
AN:
60334
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.477
Heterozygous variant carriers
0
31
62
94
125
156
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
20
40
60
80
100
<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:
0.000315
AC:
48
AN:
152190
Hom.:
0
Cov.:
31
AF XY:
0.000282
AC XY:
21
AN XY:
74412
show subpopulations
African (AFR)
AF:
0.000145
AC:
6
AN:
41520
American (AMR)
AF:
0.000393
AC:
6
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.000864
AC:
3
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5172
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000471
AC:
32
AN:
68012
Other (OTH)
AF:
0.000473
AC:
1
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.477
Heterozygous variant carriers
0
3
6
9
12
15
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:
0.000448
Hom.:
1
Bravo
AF:
0.000295
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.000778
AC:
3
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000349
AC:
3
ExAC
AF:
0.000428
AC:
52
EpiCase
AF:
0.00147
EpiControl
AF:
0.00107

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:7
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:4
Oct 01, 2016
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Breakthrough Genomics, Breakthrough Genomics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

Nov 11, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 323 of the TUBA8 protein (p.Val323Met). This variant is present in population databases (rs151102020, gnomAD 0.05%), and has an allele count higher than expected for a pathogenic variant. This variant has not been reported in the literature in individuals affected with TUBA8-related conditions. ClinVar contains an entry for this variant (Variation ID: 425280). 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) indicates that this missense variant is not expected to disrupt TUBA8 protein function with a negative predictive value of 80%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Jul 11, 2022
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Oct 28, 2015
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Macrothrombocytopenia, isolated, 2, autosomal dominant Uncertain:1
Apr 04, 2022
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Polymicrogyria with optic nerve hypoplasia Uncertain:1
Aug 17, 2018
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.95
BayesDel_addAF
Uncertain
0.030
T
BayesDel_noAF
Pathogenic
0.16
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.58
.;D;T
Eigen
Pathogenic
0.94
Eigen_PC
Pathogenic
0.93
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.91
D;D;D
M_CAP
Uncertain
0.12
D
MetaRNN
Uncertain
0.43
T;T;T
MetaSVM
Uncertain
0.59
D
MutationAssessor
Uncertain
2.3
.;M;.
PhyloP100
10
PrimateAI
Pathogenic
0.89
D
PROVEAN
Benign
-2.3
N;N;N
REVEL
Pathogenic
0.69
Sift
Pathogenic
0.0
.;D;D
Sift4G
Uncertain
0.055
T;T;T
Polyphen
1.0
.;D;D
Vest4
0.84
MVP
0.98
MPC
0.89
ClinPred
0.14
T
GERP RS
5.7
PromoterAI
0.024
Neutral
Varity_R
0.68
gMVP
0.75
Mutation Taster
=78/22
polymorphism

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: rs151102020; hg19: chr22-18609712; API