rs1057517081

Variant names:

• chr3-120633316-CTC-TA
• rs1057517081
• NM_000187.4:c.1017_1019delGAGinsTA

Variant summary

Our verdict is Pathogenic. Variant got 22 ACMG points: 22P and 0B. PVS1 PS1 PM2 PP5_Very_Strong

The NM_000187.4(HGD):​c.1017_1019delGAGinsTA​(p.Met339IlefsTer30) variant causes a frameshift, missense 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 (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Pathogenic in Lovd.

• Frequency: Genomes: not found (cov: 32)
• Consequence: HGD NM_000187.4 frameshift, missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 7.40

Genes affected

HGD (HGNC:4892): (homogentisate 1,2-dioxygenase) This gene encodes the enzyme homogentisate 1,2 dioxygenase. This enzyme is involved in the catabolism of the amino acids tyrosine and phenylalanine. Mutations in this gene are the cause of the autosomal recessive metabolism disorder alkaptonuria.[provided by RefSeq, May 2010]

ACMG classification

Verdict is Pathogenic. Variant got 22 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. There are 30 pathogenic variants in the truncated region.
• PS1: Transcript NM_000187.4 (HGD) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in Lovd
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 3-120633316-CTC-TA is Pathogenic according to our data. Variant chr3-120633316-CTC-TA is described in ClinVar as [Pathogenic]. Clinvar id is 371197.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
HGD	NM_000187.4	c.1017_1019delGAGinsTA	p.Met339IlefsTer30	frameshift_variant, missense_variant	Exon 13 of 14	ENST00000283871.10	NP_000178.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HGD	ENST00000283871.10	c.1017_1019delGAGinsTA	p.Met339IlefsTer30	frameshift_variant, missense_variant	Exon 13 of 14	1	NM_000187.4	ENSP00000283871.5

Frequencies

GnomAD3 genomes Cov.: 32

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

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Alkaptonuria Pathogenic:3

-

Department Of Human Genetics, Institute Of Clinical And Translational Research, Biomedical Research Center, Slovak Academy Of Sciences

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: research

The variant was originally described in AKU patient in PMID:19862842. It has been submitted to the HGD gene mutation database (http://hgddatabase.cvtisr.sk/, DB-ID: AKU_00092). -

Jul 22, 2016

Counsyl

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Apr 13, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

HGD-related disorder Pathogenic:1

Aug 23, 2023

PreventionGenetics, part of Exact Sciences

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The HGD c.1017_1019delinsTA variant is predicted to result in a frameshift and premature protein termination (p.Met339Ilefs*30). This variant was reported in the compound heterozygous state in an individual with alkaptonuria (Vilboux et al. 2009. PubMed ID: 19862842). This variant has not been reported in a large population database (http://gnomad.broadinstitute.org), indicating this variant is rare. Frameshift variants in HGD are expected to be pathogenic. This variant is interpreted as 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: rs1057517081; hg19: chr3-120352163;