19-6495095-G-C

Variant summary

Our verdict is Benign. Variant got -14 ACMG points: 0P and 14B. BP4_Strong BP6_Moderate BS1 BS2

The NM_006087.4(TUBB4A):c.*69C>G variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000132 in 1,573,646 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★).

• Frequency:
  • Genomes: 𝑓 0.00075 (1 hom., cov: 32)
  • Exomes 𝑓: 0.000065 (0 hom.)
• Consequence: TUBB4A NM_006087.4 3_prime_UTR
• Clinical Significance: Benign criteria provided, single submitter B:2
• Conservation: PhyloP100: 0.920

Genes affected

TUBB4A (HGNC:20774): (tubulin beta 4A class IVa) This gene encodes a member of the beta tubulin family. Beta tubulins are one of two core protein families (alpha and beta tubulins) that heterodimerize and assemble to form microtubules. Mutations in this gene cause hypomyelinating leukodystrophy-6 and autosomal dominant torsion dystonia-4. Alternate splicing results in multiple transcript variants encoding different isoforms. A pseudogene of this gene is found on chromosome X. [provided by RefSeq, Jan 2014]

ACMG classification

Verdict is Benign. Variant got -14 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.87).
• BP6: Variant 19-6495095-G-C is Benign according to our data. Variant chr19-6495095-G-C is described in ClinVar as [Benign]. Clinvar id is 894183.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.000749 (114/152148) while in subpopulation AFR AF= 0.00265 (110/41520). AF 95% confidence interval is 0.00225. There are 1 homozygotes in gnomad4. There are 56 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.
• BS2: High AC in GnomAd at 114 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TUBB4A	NM_006087.4	c.*69C>G		3_prime_UTR_variant	4/4	ENST00000264071.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TUBB4A	ENST00000264071.7	c.*69C>G		3_prime_UTR_variant	4/4	1	NM_006087.4	P1

Frequencies

GnomAD3 genomes AF: 0.000750 AC: 114 AN: 152030 Hom.: 1 Cov.: 32

Gnomad AFR AF: 0.00266

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000197

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: 0.000478

GnomAD4 exome AF: 0.0000654 AC: 93 AN: 1421498 Hom.: 0 Cov.: 29 AF XY: 0.0000625 AC XY: 44 AN XY: 704406

Gnomad4 AFR exome AF: 0.00264

Gnomad4 AMR exome AF: 0.0000236

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: 9.21e-7

Gnomad4 OTH exome AF: 0.0000851

GnomAD4 genome AF: 0.000749 AC: 114 AN: 152148 Hom.: 1 Cov.: 32 AF XY: 0.000753 AC XY: 56 AN XY: 74386

Gnomad4 AFR AF: 0.00265

Gnomad4 AMR AF: 0.000197

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.000473

Alfa AF: 0.000208 Hom.: 0

Bravo AF: 0.000638

ClinVar

Significance: Benign

Submissions summary: Benign:2

Revision: criteria provided, single submitter

Submissions by phenotype

Torsion dystonia 4 Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 27, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Hypomyelinating leukodystrophy 6 Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 27, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.87
Cadd	Benign	2.5
Dann	Benign	0.77

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

LitVar

Other links and lift over

dbSNP: rs564748070; hg19: chr19-6495106;