19-6495183-G-A

Variant names:

• chr19-6495183-G-A
• rs199569370
• NM_006087.4:c.1316C>T

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_Moderate BS2

The NM_006087.4(TUBB4A):​c.1316C>T​(p.Ala439Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000211 in 1,613,684 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. 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. A439E) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000022 (0 hom.)
• Consequence: TUBB4A NM_006087.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.720
• Publications: 2 publications found

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]

TUBB4A Gene-Disease associations (from GenCC):

• hypomyelinating leukodystrophy 6

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet, Labcorp Genetics (formerly Invitae), Illumina
• TUBB4A-related neurologic disorder

  Inheritance: AD Classification: DEFINITIVE, MODERATE Submitted by: Ambry Genetics, ClinGen
• torsion dystonia 4

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Orphanet

ENSG00000268191 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -6 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.16133657).
• BS2: High AC in GnomAdExome4 at 32 AD gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_006087.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TUBB4A	NM_006087.4	MANE Select	c.1316C>T	p.Ala439Val	missense	Exon 4 of 4	NP_006078.2
	TUBB4A	NM_001289123.2		c.1469C>T	p.Ala490Val	missense	Exon 5 of 5	NP_001276052.1	M0QZL7
	TUBB4A	NM_001289127.2		c.1451C>T	p.Ala484Val	missense	Exon 5 of 5	NP_001276056.1	M0R278

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TUBB4A	ENST00000264071.7	TSL:1 MANE Select	c.1316C>T	p.Ala439Val	missense	Exon 4 of 4	ENSP00000264071.1	P04350
	TUBB4A	ENST00000598635.2	TSL:4	c.1469C>T	p.Ala490Val	missense	Exon 5 of 5	ENSP00000470627.2	M0QZL7
	TUBB4A	ENST00000597686.6	TSL:4	c.1451C>T	p.Ala484Val	missense	Exon 5 of 5	ENSP00000472375.2	M0R278

Frequencies

GnomAD3 genomes AF: 0.0000132 AC: 2 AN: 152040 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000242

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000119 AC: 3 AN: 251160 AF XY: 0.00000737

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000264

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000219 AC: 32 AN: 1461644 Hom.: 0 Cov.: 31 AF XY: 0.0000193 AC XY: 14 AN XY: 727130

African (AFR) AF: 0.00 AC: 0 AN: 33470

American (AMR) AF: 0.00 AC: 0 AN: 44712

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.0000696 AC: 6 AN: 86248

European-Finnish (FIN) AF: 0.0000187 AC: 1 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5746

European-Non Finnish (NFE) AF: 0.0000216 AC: 24 AN: 1111846

Other (OTH) AF: 0.0000166 AC: 1 AN: 60374

GnomAD4 genome AF: 0.0000132 AC: 2 AN: 152040 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74256

African (AFR) AF: 0.0000242 AC: 1 AN: 41382

American (AMR) AF: 0.00 AC: 0 AN: 15260

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5192

South Asian (SAS) AF: 0.00 AC: 0 AN: 4814

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10606

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68000

Other (OTH) AF: 0.00 AC: 0 AN: 2090

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000113

ExAC AF: 0.00000824 AC: 1

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Hypomyelinating leukodystrophy 6 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.080
BayesDel_addAF	Benign	-0.19	T
BayesDel_noAF	Benign	-0.51
CADD	Benign	20
DANN	Benign	0.93
DEOGEN2	Benign	0.028	T
Eigen	Benign	-0.046
Eigen_PC	Benign	-0.089
FATHMM_MKL	Benign	0.63	D
LIST_S2	Uncertain	0.94	D
M_CAP	Uncertain	0.15	D
MetaRNN	Benign	0.16	T
MetaSVM	Benign	-0.73	T
MutationAssessor	Benign	0.76	N
PhyloP100		0.72
PrimateAI	Uncertain	0.59	T
PROVEAN	Benign	-0.36	N
REVEL	Benign	0.16
Sift4G	Benign	0.29	T
Polyphen		0.96	D
Vest4		0.081
MutPred		0.31		Gain of helix (P = 0.0425)
MVP		0.88
MPC		1.4
ClinPred		0.24	T
GERP RS		2.0
Varity_R		0.12
gMVP		0.89
Mutation Taster		=79/21	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

Other links and lift over

dbSNP: rs199569370; hg19: chr19-6495194;