rs118204109

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2PP3_StrongPP5_Very_Strong

The NM_000190.4(HMBS):c.601C>T(p.Arg201Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000168 in 1,550,004 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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

HMBS
NM_000190.4 missense

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:7

Conservation

PhyloP100: 2.00

Variant links:

Genes affected

HMBS (HGNC:4982): (hydroxymethylbilane synthase) This gene encodes a member of the hydroxymethylbilane synthase superfamily. The encoded protein is the third enzyme of the heme biosynthetic pathway and catalyzes the head to tail condensation of four porphobilinogen molecules into the linear hydroxymethylbilane. Mutations in this gene are associated with the autosomal dominant disease acute intermittent porphyria. Alternatively spliced transcript variants encoding different isoforms have been described. [provided by RefSeq, Jul 2008]

HMBS links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.993

PP5

Variant 11-119091515-C-T is Pathogenic according to our data. Variant chr11-119091515-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1462.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
HMBS	NM_000190.4 link	c.601C>T	p.Arg201Trp	missense_variant	Exon 9 of 14	ENST00000652429.1	NP_000181.2	P08397-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HMBS	ENST00000652429.1 link	c.601C>T	p.Arg201Trp	missense_variant	Exon 9 of 14		NM_000190.4	ENSP00000498786.1		P08397-1

Frequencies

GnomAD3 genomes

AF:

0.0000394

AC:

AN:

152246

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

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:

0.0000735

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000256

AC:

AN:

155962

Hom.:

AF XY:

0.0000365

AC XY:

AN XY:

82192

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000404

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000885

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000332

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000143

AC:

AN:

1397758

Hom.:

Cov.:

AF XY:

0.0000145

AC XY:

AN XY:

689526

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000560

Gnomad4 SAS exome

AF:

0.0000126

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000158

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000394

AC:

AN:

152246

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74386

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000735

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000831

Hom.:

Bravo

AF:

0.0000378

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Acute intermittent porphyria

Pathogenic:3

Juno Genomics, Hangzhou Juno Genomics, Inc

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

PM2_Supporting+PS3_Moderate+PS4_Moderate+PP4 -

Jan 01, 1994

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Dec 18, 2018

Illumina Laboratory Services, Illumina

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The HMBS c.601C>T (p.Arg201Trp) missense variant has been reported in at least four studies in which it was found in a heterozygous state in at least 12 individuals with acute intermittent porphyria or hydroxymethylbilane synthase deficiency.(Lundin et al. 1994; Chen et al. 1994; Floderus et al. 2002; Cerbino et al. 2015). At least seven of these individuals were from one family in which the variant displayed segregation with disease (Lundin et al. 1994). Control data are unavailable for the p.Arg201Trp variant, which is reported at a frequency of 0.000027 in the total population of the Genome Aggregation Database. Functional studies conducted in E. coli indicate the variant form of the protein exhibited reduced enzymatic activity and stability compared to the wild type (Chen et al. 1994). Based on the collective evidence, the p.Arg201Trp variant is classified as pathogenic for hydroxymethylbilane synthase deficiency. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. -

not provided

Pathogenic:3

Nov 15, 2019

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; This variant is associated with the following publications: (PMID: 12372055, 7962538, 8270256, 26075277, 11055586) -

Dec 21, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 201 of the HMBS protein (p.Arg201Trp). This variant is present in population databases (rs118204109, gnomAD 0.01%). This missense change has been observed in individual(s) with acute intermitent porphyria (PMID: 7962538, 8270256, 26075277). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 1462). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt HMBS protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects HMBS function (PMID: 7962538, 11055586). For these reasons, this variant has been classified as Pathogenic. -

Jun 23, 2022

Mayo Clinic Laboratories, Mayo Clinic

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

PP3, PP4, PM2, PS3 -

Encephalopathy, porphyria-related

Pathogenic:1

Watson Genetic Lab

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.66

BayesDel_addAF

Pathogenic

0.39

BayesDel_noAF

Pathogenic

0.53

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.99

.;D;.;.;D;.;.;D;.;.;.;.;.

Eigen

Uncertain

0.34

Eigen_PC

Benign

0.21

FATHMM_MKL

Pathogenic

0.97

M_CAP

Pathogenic

0.53

MetaRNN

Pathogenic

0.99

D;D;D;D;D;D;D;D;D;D;D;D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Pathogenic

3.6

.;H;.;.;.;.;H;.;.;.;.;.;.

PrimateAI

Uncertain

0.64

PROVEAN

Pathogenic

-7.7

.;D;D;D;D;.;D;D;.;D;D;D;.

REVEL

Pathogenic

0.93

Sift

Pathogenic

0.0

.;D;D;D;D;.;D;D;.;D;D;D;.

Sift4G

Pathogenic

0.0

.;D;D;D;D;.;D;D;.;D;D;D;.

Polyphen

1.0

.;D;D;.;.;.;.;D;.;D;.;D;D

Vest4

0.90, 0.91, 0.88, 0.90, 0.86, 0.91

MutPred

0.92

.;Loss of MoRF binding (P = 0.0825);.;.;.;.;Loss of MoRF binding (P = 0.0825);.;.;.;.;.;.;

MVP

0.98

MPC

1.2

ClinPred

0.99

GERP RS

1.5

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.96

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over