rs752919200

Positions:

• chr17-3658151-C-CA

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.829dupA​(p.Thr277fs) variant causes a frameshift change. The variant allele was found at a frequency of 0.00000274 in 1,459,928 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 35)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: CTNS NM_004937.3 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 5.67

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]

CTNS (HGNC:):

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 17-3658151-C-CA is Pathogenic according to our data. Variant chr17-3658151-C-CA is described in ClinVar as [Pathogenic]. Clinvar id is 551290.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.829dupA	p.Thr277fs	frameshift_variant	10/12	ENST00000046640.9	NP_004928.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CTNS	ENST00000046640.9	c.829dupA	p.Thr277fs	frameshift_variant	10/12	1	NM_004937.3	ENSP00000046640.4

Frequencies

GnomAD3 genomes Cov.: 35

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251096 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135836

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

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: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1459928 Hom.: 0 Cov.: 35 AF XY: 0.00000275 AC XY: 2 AN XY: 726304

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 0.00

GnomAD4 genome Cov.: 35

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Nephropathic cystinosis Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Mar 29, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Jan 01, 2024	- -

Juvenile nephropathic cystinosis;C2931013:Ocular cystinosis;C2931187:Nephropathic cystinosis Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Feb 14, 2022

- -

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

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 04, 2021

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 551290). This premature translational stop signal has been observed in individual(s) with clinical features of nephropathic cystinosis (PMID: 22664570, 24464559, 26565940, 28893421). In at least one individual the data is consistent with the variant being in trans (on the opposite chromosome) from a pathogenic variant. This variant is present in population databases (rs752919200, ExAC 0.002%). This sequence change creates a premature translational stop signal (p.Thr277Asnfs*19) 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). -

Cystinosis Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Natera, Inc.

Oct 07, 2020

- -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs752919200; hg19: chr17-3561445;