rs886041369

Variant names:

• chrX-22227520-G-A
• rs886041369
• NM_000444.6:c.1979G>A

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000444.6(PHEX):​c.1979G>A​(p.Trp660*) variant causes a stop gained 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. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 23)
• Consequence: PHEX NM_000444.6 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 8.63
• Publications: 1 publications found

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]

PTCHD1-AS (HGNC:37703): (PTCHD1 antisense RNA (head to head))

ACMG classification

Our verdict: Pathogenic. The variant received 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 X-22227520-G-A is Pathogenic according to our data. Variant chrX-22227520-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 280082.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PHEX	NM_000444.6	c.1979G>A	p.Trp660*	stop_gained	Exon 20 of 22	ENST00000379374.5	NP_000435.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PHEX	ENST00000379374.5	c.1979G>A	p.Trp660*	stop_gained	Exon 20 of 22	1	NM_000444.6	ENSP00000368682.4

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 23

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Oct 26, 2018

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The W660X nonsense variant in the PHEX gene has been reported previously in association with X-linked hypophosphatemic rickets (Francis et al., 1997). This variant is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. The variant was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. Therefore, we consider this variant to be pathogenic. -

Dec 17, 2019

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. Loss-of-function variants in PHEX are known to be pathogenic (PMID: 9097956, 9106524, 19219621). This variant has been observed in an individual affected with hypophosphatemic rickets (PMID: 9199930). ClinVar contains an entry for this variant (Variation ID: 280082). This variant is not present in population databases (ExAC no frequency). This sequence change creates a premature translational stop signal (p.Trp660*) in the PHEX gene. It is expected to result in an absent or disrupted protein product. -

Familial X-linked hypophosphatemic vitamin D refractory rickets Pathogenic:1

Jun 12, 2017

Institute of Human Genetics Munich, TUM University Hospital

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hypophosphatemic rickets Pathogenic:1

Mar 07, 2022

Laboratory of Cyto-molecular Genetics, Department of Anatomy, All India Institute of Medical Sciences (AIIMS), New Delhi

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.74	D
BayesDel_noAF	Pathogenic	0.65
CADD	Pathogenic	50
DANN	Uncertain	1.0
FATHMM_MKL	Pathogenic	0.98	D
PhyloP100		8.6
Vest4		0.97
GERP RS		5.4
Mutation Taster		=0/200	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs886041369; hg19: chrX-22245637;