rs281865348

Positions:

• chrX-18644429-C-A
• chrX-18644429-C-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PVS1 PM2 PP3_Strong PP5_Moderate

The NM_000330.4(RS1):​c.522+1G>T variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 23)
• Consequence: RS1 NM_000330.4 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, single submitter P:1 O:1
• Conservation: PhyloP100: 7.32

Genes affected

RS1 (HGNC:10457): (retinoschisin 1) This gene encodes an extracellular protein that plays a crucial role in the cellular organization of the retina. The encoded protein is assembled and secreted from photoreceptors and bipolar cells as a homo-oligomeric protein complex. Mutations in this gene are responsible for X-linked retinoschisis, a common, early-onset macular degeneration in males that results in a splitting of the inner layers of the retina and severe loss in vision. [provided by RefSeq, Oct 2008]

CDKL5 (HGNC:11411): (cyclin dependent kinase like 5) This gene is a member of Ser/Thr protein kinase family and encodes a phosphorylated protein with protein kinase activity. Mutations in this gene have been associated with X-linked infantile spasm syndrome (ISSX), also known as X-linked West syndrome, and Rett syndrome (RTT). Alternate transcriptional splice variants have been characterized. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 16 ACMG points.

• PVS1: Splicing variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant X-18644429-C-A is Pathogenic according to our data. Variant chrX-18644429-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 98980.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chrX-18644429-C-A is described in Lovd as [Pathogenic]. Variant chrX-18644429-C-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
RS1	NM_000330.4	c.522+1G>T		splice_donor_variant		ENST00000379984.4
RS1	XM_047442337.1	c.426+1G>T		splice_donor_variant
CDKL5	NM_001037343.2	c.2714-1578C>A		intron_variant
CDKL5	NM_003159.3	c.2714-1578C>A		intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
RS1	ENST00000379984.4	c.522+1G>T		splice_donor_variant		1	NM_000330.4	P1
CDKL5	ENST00000379989.6	c.2714-1578C>A		intron_variant		1
CDKL5	ENST00000379996.7	c.2714-1578C>A		intron_variant		1
RS1	ENST00000476595.1	n.1013+1G>T		splice_donor_variant, non_coding_transcript_variant		1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 23

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1 Other:1

not provided, no classification provided	literature only	Retina International	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jul 07, 2023	For these reasons, this variant has been classified as Pathogenic. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 98980). Disruption of this splice site has been observed in individuals with retinoschisis (PMID: 9618178, 12920343, 23288992, 27032803). This variant is not present in population databases (gnomAD no frequency). This sequence change affects a donor splice site in intron 5 of the RS1 gene. While this variant is not anticipated to result in nonsense mediated decay, it likely alters RNA splicing and results in a disrupted protein product. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.44	D
BayesDel_noAF	Pathogenic	0.39
CADD	Pathogenic	36
DANN	Uncertain	1.0
FATHMM_MKL	Pathogenic	0.98	D
MutationTaster	Benign	1.0	D;D;D
GERP RS		4.9

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.90		Position offset: 2
DS_DL_spliceai		1.0		Position offset: 1

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

Publications

LitVar

Other links and lift over

dbSNP: rs281865348; hg19: chrX-18662549;