22-18110861-CAGCGATGGTG-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_ModeratePM2

The NM_018943.3(TUBA8):​c.-2_3+5del variant causes a splice donor, splice donor region, coding sequence, 5 prime UTR, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000143 in 1,394,582 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

TUBA8
NM_018943.3 splice_donor, splice_donor_region, coding_sequence, 5_prime_UTR, intron

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 2.03
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.043703705 fraction of the gene. Cryptic splice site detected, with MaxEntScore 7.5, offset of -29, new splice context is: gagGTgcgc. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TUBA8NM_018943.3 linkuse as main transcriptc.-2_3+5del splice_donor_variant, splice_donor_region_variant, coding_sequence_variant, 5_prime_UTR_variant, intron_variant 1/5 ENST00000330423.8 NP_061816.1
TUBA8NM_001193414.2 linkuse as main transcriptc.-196+25_-196+34del intron_variant NP_001180343.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
TUBA8ENST00000330423.8 linkuse as main transcriptc.-2_3+5del splice_donor_variant, splice_donor_region_variant, coding_sequence_variant, 5_prime_UTR_variant, intron_variant 1/51 NM_018943.3 ENSP00000333326 P1Q9NY65-1
ENST00000623543.1 linkuse as main transcriptn.20284_20293del non_coding_transcript_exon_variant 1/1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD3 exomes
AF:
0.0000132
AC:
2
AN:
151680
Hom.:
0
AF XY:
0.0000244
AC XY:
2
AN XY:
81826
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000785
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000143
AC:
2
AN:
1394582
Hom.:
0
AF XY:
0.00000290
AC XY:
2
AN XY:
689138
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000547
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
32
Bravo
AF:
0.00000378

ClinVar

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

Submissions by phenotype

not provided Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpSep 30, 2023In 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. ClinVar contains an entry for this variant (Variation ID: 1916347). This variant has not been reported in the literature in individuals affected with TUBA8-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.008%). This sequence change affects the initiator methionine of the TUBA8 mRNA. The next in-frame methionine is located at codon 67. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

Splicing

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: rs1160947614; hg19: chr22-18593627; API