chr16-89935589-C-A

Variant names:

• chr16-89935589-C-A
• NM_006086.4:c.1138C>A

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM2 PM5 PP2 PP3_Strong PP5_Moderate

The NM_006086.4(TUBB3):​c.1138C>A​(p.Arg380Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R380C) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TUBB3 NM_006086.4 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 2.10

Genes affected

TUBB3 (HGNC:20772): (tubulin beta 3 class III) This gene encodes a class III member of the beta tubulin protein family. Beta tubulins are one of two core protein families (alpha and beta tubulins) that heterodimerize and assemble to form microtubules. This protein is primarily expressed in neurons and may be involved in neurogenesis and axon guidance and maintenance. Mutations in this gene are the cause of congenital fibrosis of the extraocular muscles type 3. Alternate splicing results in multiple transcript variants. A pseudogene of this gene is found on chromosome 6. [provided by RefSeq, Oct 2010]

ENSG00000198211 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr16-89935589-C-T is described in Lovd as [Pathogenic].
• PP2: Missense variant in the TUBB3 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 45 curated pathogenic missense variants (we use a threshold of 10). The gene has 6 curated benign missense variants. Gene score misZ: 4.5786 (above the threshold of 3.09). Trascript score misZ: 5.665 (above the threshold of 3.09). GenCC associations: The gene is linked to tubulinopathy-associated dysgyria, complex cortical dysplasia with other brain malformations 1, congenital fibrosis of extraocular muscles, fibrosis of extraocular muscles, congenital, 3A, with or without extraocular involvement.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.943
• PP5: Variant 16-89935589-C-A is Pathogenic according to our data. Variant chr16-89935589-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2499586.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TUBB3	NM_006086.4	c.1138C>A	p.Arg380Ser	missense_variant	Exon 4 of 4	ENST00000315491.12	NP_006077.2
TUBB3	NM_001197181.2	c.922C>A	p.Arg308Ser	missense_variant	Exon 4 of 4		NP_001184110.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TUBB3	ENST00000315491.12	c.1138C>A	p.Arg380Ser	missense_variant	Exon 4 of 4	1	NM_006086.4	ENSP00000320295.7
ENSG00000198211	ENST00000556922.1	c.2179C>A	p.Arg727Ser	missense_variant	Exon 5 of 5	2		ENSP00000451560.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Complex cortical dysplasia with other brain malformations 1 Pathogenic:1

Apr 20, 2023

Duke University Health System Sequencing Clinic, Duke University Health System

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: research

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.36
CADD	Pathogenic	28
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.88	.;.;D
Eigen	Pathogenic	0.79
Eigen_PC	Uncertain	0.66
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Benign	0.72	T;T;T
M_CAP	Pathogenic	0.78	D
MetaRNN	Pathogenic	0.94	D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.5	.;.;H
PrimateAI	Pathogenic	0.90	D
PROVEAN	Pathogenic	-4.6	D;D;D
REVEL	Pathogenic	0.80
Sift	Uncertain	0.0010	D;.;.
Sift4G	Pathogenic	0.0010	D;D;D
Polyphen		1.0	.;.;D
Vest4		0.86
MutPred		0.76		.;.;Loss of MoRF binding (P = 0.0258);
MVP		1.0
MPC		2.9
ClinPred		1.0	D
GERP RS		4.7
Varity_R		0.99
gMVP		0.99

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr16-90001997;