17-59676934-T-TTTTTTTCC

Position:

• chr17-59676934-T-TTTTTTTCC

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PVS1_Moderate PM2 BP6_Moderate

The NM_004859.4(CLTC):​c.2562-10_2562-3dupTTTTTCCT variant causes a splice acceptor, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000014 in 1,426,884 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CLTC NM_004859.4 splice_acceptor, intron
• Clinical Significance: Likely benign criteria provided, single submitter B:2
• Conservation: PhyloP100: 0.171

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 Uncertain_significance. Variant got 2 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.04653938 fraction of the gene. Cryptic splice site detected, with MaxEntScore 10, offset of 0 (no position change), new splice context is: cttttttccttttttcctAGatt. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• BP6: Variant 17-59676934-T-TTTTTTTCC is Benign according to our data. Variant chr17-59676934-T-TTTTTTTCC is described in ClinVar as [Likely_benign]. Clinvar id is 2805712.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CLTC	NM_004859.4	c.2562-10_2562-3dupTTTTTCCT		splice_acceptor_variant, intron_variant		ENST00000269122.8	NP_004850.1
CLTC	NM_001288653.2	c.2574-10_2574-3dupTTTTTCCT		splice_acceptor_variant, intron_variant			NP_001275582.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CLTC	ENST00000269122.8	c.2562-20_2562-19insTTTTTTCC		intron_variant		1	NM_004859.4	ENSP00000269122.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000140 AC: 2 AN: 1426884 Hom.: 0 Cov.: 27 AF XY: 0.00 AC XY: 0 AN XY: 711988

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000451

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000756

ClinVar

Significance: Likely benign

Submissions summary: Benign:2

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 14, 2023

- -

CLTC-related disorder Benign:1

Likely benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Feb 13, 2023

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs2032979421; hg19: chr17-57754295;