rs118204099

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1PM2PM5PP3_Moderate

The NM_000190.4(HMBS):​c.734T>C​(p.Leu245Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,876 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L245R) has been classified as Pathogenic.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

HMBS
NM_000190.4 missense

Scores

13
2
3

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: 7.80

Publications

0 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 8 ACMG points.

PM1
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 10 uncertain in NM_000190.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr11-119092486-T-G is described in ClinVar as Pathogenic. ClinVar VariationId is 1450.Status of the report is no_assertion_criteria_provided, 0 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.915

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HMBSNM_000190.4 linkc.734T>C p.Leu245Pro missense_variant Exon 11 of 14 ENST00000652429.1 NP_000181.2 P08397-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HMBSENST00000652429.1 linkc.734T>C p.Leu245Pro missense_variant Exon 11 of 14 NM_000190.4 ENSP00000498786.1 P08397-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461876
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
727242
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53408
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1112006
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.93
BayesDel_addAF
Pathogenic
0.56
D
BayesDel_noAF
Pathogenic
0.56
CADD
Pathogenic
31
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.88
.;D;.;.;T;.;.;.;.
Eigen
Pathogenic
0.92
Eigen_PC
Pathogenic
0.84
FATHMM_MKL
Pathogenic
0.98
D
M_CAP
Pathogenic
0.50
D
MetaRNN
Pathogenic
0.92
D;D;D;D;D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.1
.;H;.;.;.;.;.;.;.
PhyloP100
7.8
PrimateAI
Uncertain
0.75
T
PROVEAN
Uncertain
-4.0
.;D;D;.;D;.;.;D;.
REVEL
Pathogenic
0.93
Sift
Benign
0.10
.;T;T;.;T;.;.;T;.
Sift4G
Benign
0.099
.;T;T;.;T;.;.;T;.
Polyphen
1.0
.;D;.;.;D;.;.;.;.
Vest4
0.99, 0.99, 0.98
MutPred
0.67
.;Loss of stability (P = 0.038);.;.;.;.;.;.;.;
MVP
0.95
MPC
1.5
ClinPred
0.99
D
GERP RS
5.2
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.99
Mutation Taster
=5/95
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.070
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: rs118204099; hg19: chr11-118963196; API