rs879255615

Positions:

• chr17-3655094-CA-C

Variant summary

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

The NM_004937.3(CTNS):​c.323del​(p.Gln108ArgfsTer10) variant causes a frameshift change involving the alteration of a non-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: 31)
• Consequence: CTNS NM_004937.3 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 2.97

Genes affected

CTNS (HGNC:2518): (cystinosin, lysosomal cystine transporter) This gene encodes a seven-transmembrane domain protein that functions to transport cystine out of lysosomes. Its activity is driven by the H+ electrochemical gradient of the lysosomal membrane. Mutations in this gene cause cystinosis, a lysosomal storage disorder. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2009]

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 17-3655094-CA-C is Pathogenic according to our data. Variant chr17-3655094-CA-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 253205.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CTNS	NM_004937.3	c.323del	p.Gln108ArgfsTer10	frameshift_variant	6/12	ENST00000046640.9	NP_004928.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CTNS	ENST00000046640.9	c.323del	p.Gln108ArgfsTer10	frameshift_variant	6/12	1	NM_004937.3	ENSP00000046640	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Nephropathic cystinosis Pathogenic:3

Pathogenic, no assertion criteria provided	clinical testing	Rasad Genetic Department, Rasad Pathobiology and Genetic Laboratory	Jan 01, 2020	- -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Feb 22, 2022	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Jan 11, 2018	- -

Juvenile nephropathic cystinosis;C0950123:Inborn genetic diseases;C2931013:Ocular cystinosis Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 24, 2023

This sequence change creates a premature translational stop signal (p.Gln108Argfs*10) in the CTNS gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in CTNS are known to be pathogenic (PMID: 9537412, 27102039). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with cystinosis (PMID: 28238446, 35513889). ClinVar contains an entry for this variant (Variation ID: 253205). For these reasons, this variant has been classified as Pathogenic. -

Cystinosis Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

IUMS Hospital Medical Genetics Lab, Iran University of Medical Sciences

-

- -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs879255615; hg19: chr17-3558388;