chrX-22168390-G-C

Position:

• chrX-22168390-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_000444.6(PHEX):​c.1482+1G>C 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: PHEX NM_000444.6 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.53

Genes affected

PHEX (HGNC:8918): (phosphate regulating endopeptidase X-linked) The protein encoded by this gene is a transmembrane endopeptidase that belongs to the type II integral membrane zinc-dependent endopeptidase family. The protein is thought to be involved in bone and dentin mineralization and renal phosphate reabsorption. Mutations in this gene cause X-linked hypophosphatemic rickets. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2013]

PHEX-AS1 (HGNC:40445): (PHEX antisense RNA 1)

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.034222223 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-22168390-G-C is Pathogenic according to our data. Variant chrX-22168390-G-C is described in ClinVar as [Pathogenic]. Clinvar id is 940437.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chrX-22168390-G-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PHEX	NM_000444.6	c.1482+1G>C		splice_donor_variant		ENST00000379374.5	NP_000435.3
PHEX-AS1	NR_046639.1	n.1267+1404C>G		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PHEX	ENST00000379374.5	c.1482+1G>C		splice_donor_variant		1	NM_000444.6	ENSP00000368682	P1
PHEX-AS1	ENST00000424650.1	n.1267+1404C>G		intron_variant, non_coding_transcript_variant		2

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 23

GnomAD4 genome Cov.: 23

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 26, 2023

For these reasons, this variant has been classified as Pathogenic. 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: 940437). This variant is also known as IVS13+1G>C. Disruption of this splice site has been observed in individuals with hypophosphatemic rickets (PMID: 9768674, 11502829, 23079138). This variant is not present in population databases (gnomAD no frequency). This sequence change affects a donor splice site in intron 13 of the PHEX gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in PHEX are known to be pathogenic (PMID: 9097956, 9106524, 19219621). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.74	D
BayesDel_noAF	Pathogenic	0.18
CADD	Pathogenic	29
DANN	Uncertain	0.99
FATHMM_MKL	Pathogenic	0.98	D
MutationTaster	Benign	1.0	D;D;D;D
GERP RS		4.8

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
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: rs1064793228; hg19: chrX-22186507;