NM_000190.4:c.601C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 7P and 1B. PM1PP3_StrongPP5BS2_Supporting

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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R201Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

HMBS
NM_000190.4 missense

Scores

13
3
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:7U:1

Conservation

PhyloP100: 2.00

Publications

14 publications found
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 Gene-Disease associations (from GenCC):
  • acute intermittent porphyria
    Inheritance: SD, AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in NM_000190.4
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 Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1462.
BS2
High AC in GnomAd4 at 6 SD,AD gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000190.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
HMBS
NM_000190.4
MANE Select
c.601C>Tp.Arg201Trp
missense
Exon 9 of 14NP_000181.2
HMBS
NM_001425056.1
c.601C>Tp.Arg201Trp
missense
Exon 9 of 14NP_001411985.1
HMBS
NM_001425057.1
c.583C>Tp.Arg195Trp
missense
Exon 9 of 14NP_001411986.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
HMBS
ENST00000652429.1
MANE Select
c.601C>Tp.Arg201Trp
missense
Exon 9 of 14ENSP00000498786.1
HMBS
ENST00000392841.1
TSL:1
c.550C>Tp.Arg184Trp
missense
Exon 9 of 14ENSP00000376584.1
HMBS
ENST00000545621.5
TSL:1
n.*496C>T
non_coding_transcript_exon
Exon 9 of 10ENSP00000444849.1

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152246
Hom.:
0
Cov.:
32
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
GnomAD2 exomes
AF:
0.0000256
AC:
4
AN:
155962
AF XY:
0.0000365
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000332
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000143
AC:
20
AN:
1397758
Hom.:
0
Cov.:
30
AF XY:
0.0000145
AC XY:
10
AN XY:
689526
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
31562
American (AMR)
AF:
0.00
AC:
0
AN:
35704
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25176
East Asian (EAS)
AF:
0.0000560
AC:
2
AN:
35736
South Asian (SAS)
AF:
0.0000126
AC:
1
AN:
79216
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
49164
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5696
European-Non Finnish (NFE)
AF:
0.0000158
AC:
17
AN:
1077558
Other (OTH)
AF:
0.00
AC:
0
AN:
57946
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.440
Heterozygous variant carriers
0
1
2
4
5
6
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:
0.0000394
AC:
6
AN:
152246
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74386
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41470
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5204
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000829
Hom.:
0
Bravo
AF:
0.0000378

ClinVar

ClinVar submissions as Germline

Significance:Conflicting classifications of pathogenicity
Revision:criteria provided, conflicting classifications
View on ClinVar
Pathogenic
VUS
Benign
Condition
3
1
-
Acute intermittent porphyria (4)
3
-
-
not provided (3)
1
-
-
Encephalopathy, porphyria-related (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.66
BayesDel_addAF
Pathogenic
0.39
D
BayesDel_noAF
Pathogenic
0.53
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.99
D
Eigen
Uncertain
0.34
Eigen_PC
Benign
0.21
FATHMM_MKL
Pathogenic
0.97
D
M_CAP
Pathogenic
0.53
D
MetaRNN
Pathogenic
0.99
D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.6
H
PhyloP100
2.0
PrimateAI
Uncertain
0.64
T
PROVEAN
Pathogenic
-7.7
D
REVEL
Pathogenic
0.93
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.90
MutPred
0.92
Loss of MoRF binding (P = 0.0825)
MVP
0.98
MPC
1.2
ClinPred
0.99
D
GERP RS
1.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.96
Mutation Taster
=0/100
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: rs118204109; hg19: chr11-118962225; API