rs376543555

Positions:

• chr15-42775204-A-G

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_Strong BP6_Very_Strong BP7 BS1 BS2

The NM_173500.4(TTBK2):​c.1929T>C​(p.Ala643=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000116 in 1,614,212 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 Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.00060 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000065 (0 hom.)
• Consequence: TTBK2 NM_173500.4 synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:3
• Conservation: PhyloP100: 2.51

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]

ACMG classification

Verdict is Benign. Variant got -21 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.47).
• BP6: Variant 15-42775204-A-G is Benign according to our data. Variant chr15-42775204-A-G is described in ClinVar as [Likely_benign]. Clinvar id is 448752.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=2.51 with no splicing effect.
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.000604 (92/152342) while in subpopulation AFR AF= 0.00214 (89/41586). AF 95% confidence interval is 0.00178. There are 0 homozygotes in gnomad4. There are 34 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.
• BS2: High AC in GnomAd4 at 92 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TTBK2	NM_173500.4	c.1929T>C	p.Ala643=	synonymous_variant	13/15	ENST00000267890.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TTBK2	ENST00000267890.11	c.1929T>C	p.Ala643=	synonymous_variant	13/15	5	NM_173500.4	P1

Frequencies

GnomAD3 genomes AF: 0.000611 AC: 93 AN: 152224 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00217

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000196

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

GnomAD3 exomes AF: 0.000116 AC: 29 AN: 249436 Hom.: 0 AF XY: 0.0000739 AC XY: 10 AN XY: 135344

Gnomad AFR exome AF: 0.00162

Gnomad AMR exome AF: 0.0000869

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: 0.00000883

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000650 AC: 95 AN: 1461870 Hom.: 0 Cov.: 31 AF XY: 0.0000468 AC XY: 34 AN XY: 727244

Gnomad4 AFR exome AF: 0.00221

Gnomad4 AMR exome AF: 0.000157

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: 0.00000360

Gnomad4 OTH exome AF: 0.000166

GnomAD4 genome AF: 0.000604 AC: 92 AN: 152342 Hom.: 0 Cov.: 32 AF XY: 0.000456 AC XY: 34 AN XY: 74498

Gnomad4 AFR AF: 0.00214

Gnomad4 AMR AF: 0.000196

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: 0.00

Alfa AF: 0.000561 Hom.: 0

Bravo AF: 0.000774

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:2

Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Oct 01, 2023	TTBK2: BP4 -
Benign, criteria provided, single submitter	clinical testing	Invitae	Oct 05, 2023	- -

not specified Benign:1

Benign, criteria provided, single submitter

clinical testing

Athena Diagnostics

Dec 14, 2016

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.47
CADD	Benign	6.6
DANN	Benign	0.63

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: rs376543555; hg19: chr15-43067402;