X-22221622-A-ATGAT

Position:

• chrX-22221622-A-ATGAT

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000444.6(PHEX):​c.1779_1782dup​(p.Lys595Ter) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 2.10

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

Verdict is Pathogenic. Variant got 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-22221622-A-ATGAT is Pathogenic according to our data. Variant chrX-22221622-A-ATGAT is described in ClinVar as [Pathogenic]. Clinvar id is 280077.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
PHEX	NM_000444.6	c.1779_1782dup	p.Lys595Ter	frameshift_variant	18/22	ENST00000379374.5	NP_000435.3
PTCHD1-AS	NR_073010.2	n.1048+5847_1048+5848insATCA		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PHEX	ENST00000379374.5	c.1779_1782dup	p.Lys595Ter	frameshift_variant	18/22	1	NM_000444.6	ENSP00000368682	P1
PTCHD1-AS	ENST00000669979.1	n.325+5847_325+5848insATCA		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 23

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

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

Pathogenic, criteria provided, single submitter

clinical testing

Institute of Human Genetics Munich, Klinikum Rechts Der Isar, TU München

Nov 18, 2013

- -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Jun 28, 2016

The c.1779_1782dupTGAT variant in the PHEX gene has been reported previously as c.1783insTGAT in association with hypophosphatemic rickets (Francis et al., 1997). The duplication changes the Lysine at position 595 to a Stop codon. This pathogenic variant is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. Additionally, 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. -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs886041364; hg19: chrX-22239739;