X-134473371-GA-G

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_000194.3(HPRT1):c.42del(p.Glu14AspfsTer28) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 23)
• Consequence: HPRT1 NM_000194.3 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.51

Genes affected

HPRT1 (HGNC:5157): (hypoxanthine phosphoribosyltransferase 1) The protein encoded by this gene is a transferase, which catalyzes conversion of hypoxanthine to inosine monophosphate and guanine to guanosine monophosphate via transfer of the 5-phosphoribosyl group from 5-phosphoribosyl 1-pyrophosphate. This enzyme plays a central role in the generation of purine nucleotides through the purine salvage pathway. Mutations in this gene result in Lesch-Nyhan syndrome or gout.[provided by RefSeq, Jun 2009]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 95 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-134473371-GA-G is Pathogenic according to our data. Variant chrX-134473371-GA-G is described in ClinVar as [Pathogenic]. Clinvar id is 2921770.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
HPRT1	NM_000194.3	c.42del	p.Glu14AspfsTer28	frameshift_variant	2/9	ENST00000298556.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
HPRT1	ENST00000298556.8	c.42del	p.Glu14AspfsTer28	frameshift_variant	2/9	1	NM_000194.3	P1
HPRT1	ENST00000462974.5	n.200del		non_coding_transcript_exon_variant	2/8	3
HPRT1	ENST00000475720.1			upstream_gene_variant		3

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 24

GnomAD4 genome Cov.: 23

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Lesch-Nyhan syndrome;C0268117:Partial hypoxanthine-guanine phosphoribosyltransferase deficiency Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Dec 28, 2023

This sequence change creates a premature translational stop signal (p.Glu14Aspfs*28) in the HPRT1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in HPRT1 are known to be pathogenic (PMID: 15571220, 17027311, 22157001). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with HPRT1-related conditions. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

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

No publications associated with this variant yet.

Other links and lift over

hg19: chrX-133607401;