chr15-42746163-G-A

Variant names:

• chr15-42746163-G-A
• rs199820364
• NM_173500.4:c.3367C>T

Variant summary

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

The NM_173500.4(TTBK2):​c.3367C>T​(p.Arg1123Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000223 in 1,614,134 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts 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. R1123Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000022 (0 hom.)
• Consequence: TTBK2 NM_173500.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.73
• Publications: 0 publications found

Genes affected

TTBK2 (HGNC:19141): (tau tubulin kinase 2) This gene encodes a serine-threonine kinase that putatively phosphorylates tau and tubulin proteins. Mutations in this gene cause spinocerebellar ataxia type 11 (SCA11); a neurodegenerative disease characterized by progressive ataxia and atrophy of the cerebellum and brainstem. [provided by RefSeq, Aug 2009]

TTBK2 Gene-Disease associations (from GenCC):

• spinocerebellar ataxia type 11

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

ACMG classification

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

• BP4: Computational evidence support a benign effect (MetaRNN=0.1844059).
• BS2: High AC in GnomAdExome4 at 32 AD gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_173500.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTBK2	NM_173500.4	MANE Select	c.3367C>T	p.Arg1123Trp	missense	Exon 15 of 15	NP_775771.3

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTBK2	ENST00000267890.11	TSL:5 MANE Select	c.3367C>T	p.Arg1123Trp	missense	Exon 15 of 15	ENSP00000267890.6

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152140 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000965

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: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000120 AC: 3 AN: 249552 AF XY: 0.0000148

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000290

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000556

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000219 AC: 32 AN: 1461876 Hom.: 0 Cov.: 31 AF XY: 0.0000248 AC XY: 18 AN XY: 727246

African (AFR) AF: 0.000149 AC: 5 AN: 33480

American (AMR) AF: 0.0000224 AC: 1 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.000252 AC: 10 AN: 39700

South Asian (SAS) AF: 0.0000232 AC: 2 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.0000126 AC: 14 AN: 1112006

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152258 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74452

African (AFR) AF: 0.0000963 AC: 4 AN: 41558

American (AMR) AF: 0.00 AC: 0 AN: 15292

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5186

South Asian (SAS) AF: 0.00 AC: 0 AN: 4812

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10604

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68016

Other (OTH) AF: 0.00 AC: 0 AN: 2114

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000378

ESP6500AA AF: 0.000530 AC: 2

ESP6500EA AF: 0.00 AC: 0

ExAC AF: 0.0000248 AC: 3

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Oct 13, 2016

Athena Diagnostics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.29
BayesDel_addAF	Benign	-0.21	T
BayesDel_noAF	Benign	-0.32
CADD	Uncertain	26
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.44	T
Eigen	Uncertain	0.52
Eigen_PC	Uncertain	0.46
FATHMM_MKL	Uncertain	0.83	D
LIST_S2	Uncertain	0.90	D
M_CAP	Benign	0.034	D
MetaRNN	Benign	0.18	T
MetaSVM	Benign	-0.73	T
MutationAssessor	Benign	1.7	L
PhyloP100		2.7
PrimateAI	Uncertain	0.71	T
PROVEAN	Uncertain	-2.5	D
REVEL	Benign	0.13
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.0090	D
Polyphen		1.0	D
Vest4		0.42
MVP		0.17
MPC		0.25
ClinPred		0.69	D
GERP RS		4.0
Varity_R		0.25
gMVP		0.32
Mutation Taster		=82/18	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: rs199820364; hg19: chr15-43038361; COSMIC: COSV105088027; COSMIC: COSV105088027;