rs120074171

chr3-120638471-C-Achr3-120638471-C-Gchr3-120638471-C-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PS1 PM1 PM2 PP3_Strong

The NM_000187.4(HGD):c.990G>T(p.Arg330Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000868 in 1,613,772 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another nucleotide change resulting in same amino acid change has been previously reported as Pathogenicin ClinVar.

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: HGD NM_000187.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter P:2 U:1
• Conservation: PhyloP100: -0.343

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 12 ACMG points.

• PS1: Transcript NM_000187.4 (HGD) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar as 2627717
• PM1: In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 1 uncertain in NM_000187.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.989

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
HGD	NM_000187.4	c.990G>T	p.Arg330Ser	missense_variant	12/14	ENST00000283871.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
HGD	ENST00000283871.10	c.990G>T	p.Arg330Ser	missense_variant	12/14	1	NM_000187.4	P1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 151908 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.000379

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000239 AC: 6 AN: 251314 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135818

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.000231

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000684 AC: 10 AN: 1461746 Hom.: 0 Cov.: 32 AF XY: 0.00000550 AC XY: 4 AN XY: 727188

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.000169

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152026 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74284

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.000379

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000756

ExAC AF: 0.0000247 AC: 3

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:2 Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Alkaptonuria Pathogenic:2 Uncertain:1

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Jul 27, 2022	In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 3167). This missense change has been observed in individual(s) with alkaptonuria (PMID: 10594001, 30737480, 31927521). This variant is present in population databases (rs120074171, gnomAD 0.03%). This sequence change replaces arginine, which is basic and polar, with serine, which is neutral and polar, at codon 330 of the HGD protein (p.Arg330Ser). -
Pathogenic, no assertion criteria provided	research	Department Of Human Genetics, Institute Of Clinical And Translational Research, Biomedical Research Center, Slovak Academy Of Sciences	-	The variant was originally described in AKU patient in PMID:10594001. It has been submitted to the HGD gene mutation database (http://hgddatabase.cvtisr.sk/, DB-ID: AKU_00088). -
Pathogenic, no assertion criteria provided	literature only	OMIM	Dec 01, 1999	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.43
Cadd	Uncertain	24
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	0.99	D
Eigen	Benign	0.16
Eigen_PC	Benign	0.044
FATHMM_MKL	Benign	0.36	N
LIST_S2	Pathogenic	0.99	D
M_CAP	Pathogenic	0.90	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.1	M
MutationTaster	Benign	1.0	A
PrimateAI	Uncertain	0.66	T
PROVEAN	Pathogenic	-5.9	D
REVEL	Pathogenic	0.84
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.019	D
Polyphen		0.98	D
Vest4		0.98
MutPred		0.94		Gain of ubiquitination at K327 (P = 0.0513);
MVP		0.93
MPC		0.42
ClinPred		0.97	D
GERP RS		2.4
Varity_R		0.96
gMVP		0.94

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

LitVar

Other links and lift over

dbSNP: rs120074171; hg19: chr3-120357318;