4-106235347-GT-GTT

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_001163435.3(TBCK):c.1370_1371insA(p.Asn457LysfsTer10) variant causes a frameshift change. The variant allele was found at a frequency of 0.0000187 in 1,606,174 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000019 (0 hom.)
• Consequence: TBCK NM_001163435.3 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 5.75

Genes affected

TBCK (HGNC:28261): (TBC1 domain containing kinase) This gene encodes a protein that contains a protein kinase domain, a Rhodanase-like domain and the Tre-2/Bub2/Cdc16 (TBC) domain. The encoded protein is thought to play a role in actin organization, cell growth and cell proliferation by regulating the mammalian target of the rapamycin (mTOR) signaling pathway. This protein may also be involved in the transcriptional regulation of the components of the mTOR complex. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Mar 2014]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 4-106235347-G-GT is Pathogenic according to our data. Variant chr4-106235347-G-GT is described in ClinVar as [Likely_pathogenic]. Clinvar id is 986992.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TBCK	NM_001163435.3	c.1370_1371insA	p.Asn457LysfsTer10	frameshift_variant	15/26	ENST00000394708.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TBCK	ENST00000394708.7	c.1370_1371insA	p.Asn457LysfsTer10	frameshift_variant	15/26	1	NM_001163435.3	P1

Frequencies

GnomAD3 genomes AF: 0.0000132 AC: 2 AN: 151430 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000387

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

GnomAD4 exome AF: 0.0000192 AC: 28 AN: 1454744 Hom.: 0 Cov.: 30 AF XY: 0.0000193 AC XY: 14 AN XY: 723680

Gnomad4 AFR exome AF: 0.0000602

Gnomad4 AMR exome AF: 0.0000452

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000508

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.0000382

Gnomad4 NFE exome AF: 0.0000162

Gnomad4 OTH exome AF: 0.0000333

GnomAD4 genome AF: 0.0000132 AC: 2 AN: 151430 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 73892

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000387

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Apr 26, 2022	Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Has not been previously published as pathogenic or benign to our knowledge -
Likely pathogenic, criteria provided, single submitter	clinical testing	Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen	Oct 23, 2020	- -

Hypotonia, infantile, with psychomotor retardation and characteristic facies 3 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Feb 02, 2022

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with hypotonia, infantile, with psychomotor delay and characteristic facies 3 (MIM#616900). (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0201 - Variant is predicted to cause nonsense-mediated decay (NMD) and loss of protein (premature termination codon is located at least 54 nucleotides upstream of the final exon-exon junction). (SP) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD (v2) <0.01 for a recessive condition (17 heterozygotes, 0 homozygotes). (SP) 0701 - Other NMD-predicted variants comparable to the one identified in this case have very strong previous evidence for pathogenicity. These variants have been reported many times as pathogenic, and observed in individuals with intellectual disability and hypotonia syndrome (DECIPHER, PMID: 27040691). (SP) 0803 - This variant has limited previous evidence of pathogenicity in an unrelated individual. This variant has been reported as likely pathogenic, and observed in a single individual with global developmental delay (ClinVar, LOVD). (SP) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1206 - This variant has been shown to be paternally inherited (by trio analysis). (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Computational scores

Source: dbNSFP v4.3

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: rs746860249; hg19: chr4-107156504;