chrX-18653435-T-G

Position:

• chrX-18653435-T-G

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 2P and 10B. PM2 BP4_Moderate BP6_Very_Strong

The ENST00000379984.4(RS1):​c.184+3218A>C variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: not found (cov: 24)
  • Exomes 𝑓: 0.0000055 (0 hom. 6 hem.)
  • Failed GnomAD Quality Control
• Consequence: RS1 ENST00000379984.4 intron
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:3
• Conservation: PhyloP100: -0.0960

Genes affected

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]

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]

ACMG classification

Verdict is Benign. Variant got -8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.07984394).
• BP6: Variant X-18653435-T-G is Benign according to our data. Variant chrX-18653435-T-G is described in ClinVar as [Likely_benign]. Clinvar id is 143813.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
RS1	NM_000330.4	c.184+3218A>C		intron_variant		ENST00000379984.4	NP_000321.1
CDKL5	NM_001037343.2	c.2984T>G	p.Phe995Cys	missense_variant	22/22		NP_001032420.1
CDKL5	NM_003159.3	c.2984T>G	p.Phe995Cys	missense_variant	21/21		NP_003150.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CDKL5	ENST00000379989.6	c.2984T>G	p.Phe995Cys	missense_variant	22/22	1		ENSP00000369325
CDKL5	ENST00000379996.7	c.2984T>G	p.Phe995Cys	missense_variant	21/21	1		ENSP00000369332
RS1	ENST00000379984.4	c.184+3218A>C		intron_variant		1	NM_000330.4	ENSP00000369320	P1
CDKL5	ENST00000673617.1	n.256T>G		non_coding_transcript_exon_variant	3/3

Frequencies

GnomAD3 genomes Cov.: 24

GnomAD3 exomes AF: 0.0000111 AC: 2 AN: 180978 Hom.: 0 AF XY: 0.0000305 AC XY: 2 AN XY: 65598

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: 0.000107

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 0.00000547 AC: 6 AN: 1097474 Hom.: 0 Cov.: 31 AF XY: 0.0000165 AC XY: 6 AN XY: 362914

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: 0.000111

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 24

ClinVar

Significance: Likely benign

Submissions summary: Benign:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:1

Likely benign, no assertion criteria provided

curation

RettBASE

Mar 13, 2014

In exon 20, affecting only the transcript lowly expressed; In silico prediction: SIFT = tolerated, MutationTaster = polymorphism, PolyPhen2 = benign, AlignGVGD = benign (C0) -

Inborn genetic diseases Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 19, 2024

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

CDKL5 disorder Benign:1

Likely benign, criteria provided, single submitter

curation

Centre for Population Genomics, CPG

Jul 22, 2024

This variant has been collected from RettBASE and curated to current modified ACMG/AMP criteria. Based on the classification scheme defined by the ClinGen Rett/Angelman-like Expert Panel for Rett/AS-like Disorders Specifications to the ACMG/AMP Variant Interpretation Guidelines VCEP 3.0, this variant is classified as likely benign. At least the following criteria are met: The allele frequency of this variant in at least one population in gnomAD is between 0.008% and 0.03% (BS1). Computational prediction analysis tools suggest no impact on gene product (REVEL score <= 0.15), The computational splicing predictor SpliceAI does not support significant splicing alteration (score of <=0.1) (BP4). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.45	T
BayesDel_noAF	Benign	-0.67
CADD	Benign	14
DANN	Benign	0.89
DEOGEN2	Benign	0.026	T;T
FATHMM_MKL	Benign	0.019	N
LIST_S2	Benign	0.41	.;T
M_CAP	Pathogenic	0.53	D
MetaRNN	Benign	0.080	T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.0	N;N
MutationTaster	Benign	1.0	N;N;N
PrimateAI	Benign	0.31	T
PROVEAN	Benign	-0.31	N;N
REVEL	Benign	0.10
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		0.0	B;B
Vest4		0.27
MutPred		0.21		Gain of catalytic residue at F995 (P = 0.0775);Gain of catalytic residue at F995 (P = 0.0775);
MVP		0.13
MPC		1.1
ClinPred		0.054	T
GERP RS		-3.2
Varity_R		0.086
gMVP		0.095

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: rs267608666; hg19: chrX-18671555;