X-134460299-GGCCGGCTCCGTTA-G

Position:

• chrX-134460299-GGCCGGCTCCGTTA-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.-12_1delGCCGGCTCCGTTA​(p.Met1fs) variant causes a frameshift, start lost 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 Likely pathogenic (★).

• Frequency: Genomes: not found (cov: 24)
• Consequence: HPRT1 NM_000194.3 frameshift, start_lost
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 2.22

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]

HPRT1 (HGNC:):

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 37 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-134460299-GGCCGGCTCCGTTA-G is Pathogenic according to our data. Variant chrX-134460299-GGCCGGCTCCGTTA-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1066190.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
HPRT1	NM_000194.3	c.-12_1delGCCGGCTCCGTTA	p.Met1fs	frameshift_variant, start_lost	1/9	ENST00000298556.8	NP_000185.1
HPRT1	NM_000194.3	c.-12_1delGCCGGCTCCGTTA		5_prime_UTR_variant	1/9	ENST00000298556.8	NP_000185.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
HPRT1	ENST00000298556.8	c.-12_1delGCCGGCTCCGTTA	p.Met1fs	frameshift_variant, start_lost	1/9	1	NM_000194.3	ENSP00000298556.7
HPRT1	ENST00000298556	c.-12_1delGCCGGCTCCGTTA		5_prime_UTR_variant	1/9	1	NM_000194.3	ENSP00000298556.7
HPRT1	ENST00000462974.5	n.-51_-39delGCCGGCTCCGTTA		upstream_gene_variant		3

Frequencies

GnomAD3 genomes Cov.: 24

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 24

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Partial hypoxanthine-guanine phosphoribosyltransferase deficiency Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Mar 01, 1989

- -

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

Likely pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 20, 2020

In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. This variant has been reported to affect HPRT1 protein function (PMID: 8125482). This variant has been observed in individual(s) with partial HPRT deficiency (PMID: 8125482, 2928313). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the ExAC database. This sequence change affects the initiator methionine of the HPRT1 mRNA. The next in-frame methionine is located at codon 43. -

Computational scores

Source: dbNSFP v4.3

Splicing

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-133594329;