3-120644419-C-T

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1PM2PM5PP2PP3_StrongPP5_Very_Strong

The NM_000187.4(HGD):​c.674G>A​(p.Arg225His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000744 in 1,613,972 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 Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R225C) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

HGD
NM_000187.4 missense

Scores

15
3
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 7.38

Publications

8 publications found
Variant links:
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]
HGD Gene-Disease associations (from GenCC):
  • alkaptonuria
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 19 ACMG points.

PM1
In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_000187.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr3-120644420-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1512988.
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 127 curated pathogenic missense variants (we use a threshold of 10). The gene has 16 curated benign missense variants. Gene score misZ: 0.28979 (below the threshold of 3.09). Trascript score misZ: 0.53625 (below the threshold of 3.09). GenCC associations: The gene is linked to alkaptonuria.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.96
PP5
Variant 3-120644419-C-T is Pathogenic according to our data. Variant chr3-120644419-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 189173.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
HGDNM_000187.4 linkc.674G>A p.Arg225His missense_variant Exon 10 of 14 ENST00000283871.10 NP_000178.2 Q93099

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HGDENST00000283871.10 linkc.674G>A p.Arg225His missense_variant Exon 10 of 14 1 NM_000187.4 ENSP00000283871.5 Q93099
HGDENST00000494453.1 linkc.92G>A p.Arg31His missense_variant Exon 2 of 5 3 ENSP00000419163.1 H7C576
HGDENST00000475447.2 linkc.200+179G>A intron_variant Intron 3 of 4 3 ENSP00000417977.2 H7C4R8
HGDENST00000492108.5 linkn.180+2554G>A intron_variant Intron 3 of 5 2 ENSP00000419838.1 H7C5G7

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152150
Hom.:
0
Cov.:
32
show subpopulations
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:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000797
AC:
2
AN:
250868
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.0000616
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000883
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000752
AC:
11
AN:
1461822
Hom.:
0
Cov.:
32
AF XY:
0.00000688
AC XY:
5
AN XY:
727220
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33478
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53394
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000719
AC:
8
AN:
1111978
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.452
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152150
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74336
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41420
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000415
Hom.:
0

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Alkaptonuria Pathogenic:5
-
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:9529363. It has been submitted to the HGD gene mutation database (http://hgddatabase.cvtisr.sk/, DB-ID: AKU_00071). -

Aug 03, 2022
Institute of Immunology and Genetics Kaiserslautern
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

ACMG Criteria: PS3, PS4_M, PM2, PM3, PM5, PP1, PP3, PP5; Variant was found in homozygous state. -

Apr 12, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense change has been observed in individual(s) with alkaptonuria (PMID: 12872836). This variant is present in population databases (rs562853291, gnomAD 0.007%). This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 225 of the HGD protein (p.Arg225His). ClinVar contains an entry for this variant (Variation ID: 189173). For these reasons, this variant has been classified as Pathogenic. This variant disrupts the p.Arg225 amino acid residue in HGD. Other variant(s) that disrupt this residue have been determined to be pathogenic (Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt HGD protein function. -

May 21, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 05, 2015
Counsyl
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.62
BayesDel_addAF
Pathogenic
0.43
D
BayesDel_noAF
Pathogenic
0.56
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.99
D
Eigen
Pathogenic
0.71
Eigen_PC
Pathogenic
0.74
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
0.99
D
M_CAP
Uncertain
0.21
D
MetaRNN
Pathogenic
0.96
D
MetaSVM
Uncertain
0.38
D
MutationAssessor
Pathogenic
3.9
H
PhyloP100
7.4
PrimateAI
Uncertain
0.71
T
PROVEAN
Pathogenic
-4.6
D
REVEL
Pathogenic
0.96
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.90
MVP
0.98
MPC
0.53
ClinPred
1.0
D
GERP RS
6.0
RBP_binding_hub_radar
0.92
RBP_regulation_power_radar
2.6
Varity_R
0.97
gMVP
0.91
Mutation Taster
=5/95
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs562853291; hg19: chr3-120363266; COSMIC: COSV105111423; COSMIC: COSV105111423; API