NM_000190.4:c.737G>A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 4P and 1B. PM1PP3_ModerateBS2_Supporting

The NM_000190.4(HMBS):​c.737G>A​(p.Arg246His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000644 in 1,614,196 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 variant affecting the same amino acid position, but resulting in a different missense (i.e. R246C) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000066 ( 0 hom. )

Consequence

HMBS
NM_000190.4 missense

Scores

11
3
3

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 9.73

Publications

8 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: AD, SD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), ClinGen, Genomics England PanelApp

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM1
In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_000190.4
PP3
MetaRNN computational evidence supports a deleterious effect, 0.845
BS2
High AC in GnomAd4 at 8 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

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
HMBS
NM_000190.4
MANE Select
c.737G>Ap.Arg246His
missense
Exon 11 of 14NP_000181.2
HMBS
NM_001425056.1
c.728G>Ap.Arg243His
missense
Exon 11 of 14NP_001411985.1
HMBS
NM_001425057.1
c.719G>Ap.Arg240His
missense
Exon 11 of 14NP_001411986.1

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
HMBS
ENST00000652429.1
MANE Select
c.737G>Ap.Arg246His
missense
Exon 11 of 14ENSP00000498786.1
HMBS
ENST00000392841.1
TSL:1
c.686G>Ap.Arg229His
missense
Exon 11 of 14ENSP00000376584.1
HMBS
ENST00000545621.5
TSL:1
n.*872G>A
non_coding_transcript_exon
Exon 10 of 10ENSP00000444849.1

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152212
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000482
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000192
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000358
AC:
9
AN:
251384
AF XY:
0.0000368
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000217
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000352
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000657
AC:
96
AN:
1461866
Hom.:
0
Cov.:
32
AF XY:
0.0000536
AC XY:
39
AN XY:
727236
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0000383
AC:
1
AN:
26136
East Asian (EAS)
AF:
0.0000756
AC:
3
AN:
39700
South Asian (SAS)
AF:
0.0000348
AC:
3
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53400
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000755
AC:
84
AN:
1112006
Other (OTH)
AF:
0.0000828
AC:
5
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.466
Heterozygous variant carriers
0
5
10
16
21
26
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.0000525
AC:
8
AN:
152330
Hom.:
0
Cov.:
32
AF XY:
0.0000537
AC XY:
4
AN XY:
74484
show subpopulations
African (AFR)
AF:
0.0000481
AC:
2
AN:
41580
American (AMR)
AF:
0.0000653
AC:
1
AN:
15304
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.519
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:
0.0000405
Hom.:
0
Bravo
AF:
0.0000302
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000412
AC:
5
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

ClinVar submissions as Germline
Significance:Uncertain significance
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
2
-
not provided (2)
-
1
-
Acute intermittent porphyria (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.17
BayesDel_addAF
Uncertain
0.13
D
BayesDel_noAF
Pathogenic
0.21
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.98
D
Eigen
Pathogenic
0.92
Eigen_PC
Pathogenic
0.88
FATHMM_MKL
Pathogenic
0.99
D
M_CAP
Pathogenic
0.50
D
MetaRNN
Pathogenic
0.85
D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.7
H
PhyloP100
9.7
PrimateAI
Benign
0.32
T
PROVEAN
Uncertain
-3.6
D
REVEL
Pathogenic
0.89
Sift
Uncertain
0.013
D
Sift4G
Benign
0.066
T
Polyphen
0.99
D
Vest4
0.65
MVP
0.82
MPC
1.2
ClinPred
0.93
D
GERP RS
5.2
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.92
Mutation Taster
=39/61
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.12
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: rs201909197; hg19: chr11-118963199; COSMIC: COSV53829174; COSMIC: COSV53829174; API