17-59677123-AAG-A

Position:

• chr17-59677123-AAG-A

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_004859.4(CLTC):​c.2737_2738del​(p.Asp913SerfsTer9) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CLTC NM_004859.4 frameshift
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.21

Genes affected

CLTC (HGNC:2092): (clathrin heavy chain) Clathrin is a major protein component of the cytoplasmic face of intracellular organelles, called coated vesicles and coated pits. These specialized organelles are involved in the intracellular trafficking of receptors and endocytosis of a variety of macromolecules. The basic subunit of the clathrin coat is composed of three heavy chains and three light chains. [provided by RefSeq, Jul 2008]

PTRH2 (HGNC:24265): (peptidyl-tRNA hydrolase 2) The protein encoded by this gene is a mitochondrial protein with two putative domains, an N-terminal mitochondrial localization sequence, and a UPF0099 domain. In vitro assays suggest that this protein possesses peptidyl-tRNA hydrolase activity, to release the peptidyl moiety from tRNA, thereby preventing the accumulation of dissociated peptidyl-tRNA that could reduce the efficiency of translation. This protein also plays a role regulating cell survival and death. It promotes survival as part of an integrin-signaling pathway for cells attached to the extracellular matrix (ECM), but also promotes apoptosis in cells that have lost their attachment to the ECM, a process called anoikos. After loss of cell attachment to the ECM, this protein is phosphorylated, is released from the mitochondria into the cytosol, and promotes caspase-independent apoptosis through interactions with transcriptional regulators. This gene has been implicated in the development and progression of tumors, and mutations in this gene have been associated with an infantile multisystem neurologic, endocrine, and pancreatic disease (INMEPD) characterized by intellectual disability, postnatal microcephaly, progressive cerebellar atrophy, hearing impairment, polyneuropathy, failure to thrive, and organ fibrosis with exocrine pancreas insufficiency (PMID: 25574476). Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Mar 2015]

ACMG classification

Verdict is Pathogenic. Variant got 12 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 17-59677123-AAG-A is Pathogenic according to our data. Variant chr17-59677123-AAG-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 817351.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr17-59677123-AAG-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CLTC	NM_004859.4	c.2737_2738del	p.Asp913SerfsTer9	frameshift_variant	17/32	ENST00000269122.8	NP_004850.1
CLTC	NM_001288653.2	c.2749_2750del	p.Asp917SerfsTer9	frameshift_variant	17/32		NP_001275582.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CLTC	ENST00000269122.8	c.2737_2738del	p.Asp913SerfsTer9	frameshift_variant	17/32	1	NM_004859.4	ENSP00000269122	P4

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Dec 05, 2018

A variant that is likely pathogenic has been identified in the CLTC gene. The c.2749_2750delGA variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. The c.2749_2750delGA variant in the CLTC gene causes a frameshift starting with codon Aspartate 917, changes this amino acid to a Serine residue and creates a premature Stop codon at position 9 of the new reading frame, denoted p.Asp917SerfsX9. This variant is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. The c.2749_2750delGA variant is not observed in large population cohorts (Lek et al., 2016). Therefore, this variant is likely pathogenic; however, the possibility that it is benign cannot be excluded. -

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: rs797044884; hg19: chr17-57754484;