17-3637312-CAG-C

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BS1_Supporting

The NM_004937.3(CTNS):c.-21_-20del variant causes a splice region, 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000388 in 152,222 control chromosomes in the GnomAD database, including 1 homozygotes. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00039 (1 hom., cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: CTNS NM_004937.3 splice_region, 5_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: 0.0950

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 Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BS1: Variant frequency is greater than expected in population sas. gnomad4 allele frequency = 0.000388 (59/152222) while in subpopulation SAS AF= 0.00892 (43/4818). AF 95% confidence interval is 0.00681. There are 1 homozygotes in gnomad4. There are 37 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CTNS	NM_004937.3	c.-21_-20del		splice_region_variant, 5_prime_UTR_variant	2/12	ENST00000046640.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CTNS	ENST00000046640.9	c.-21_-20del		splice_region_variant, 5_prime_UTR_variant	2/12	1	NM_004937.3	P1

Frequencies

GnomAD3 genomes AF: 0.000388 AC: 59 AN: 152104 Hom.: 1 Cov.: 33

Gnomad AFR AF: 0.0000724

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000655

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00871

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000441

Gnomad OTH AF: 0.000478

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 36 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 24

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

GnomAD4 genome AF: 0.000388 AC: 59 AN: 152222 Hom.: 1 Cov.: 33 AF XY: 0.000497 AC XY: 37 AN XY: 74426

Gnomad4 AFR AF: 0.0000722

Gnomad4 AMR AF: 0.000654

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00892

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000441

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000142 Hom.: 0

Bravo AF: 0.000253

Asia WGS AF: 0.00115 AC: 4 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

Submissions by phenotype

Nephropathic cystinosis Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

Cystinosis Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

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: rs550436044; hg19: chr17-3540606;