rs118204120

Variant names:

• chr11-119090212-C-T
• rs118204120
• NM_000190.4:c.445C>T

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000190.4(HMBS):​c.445C>T​(p.Arg149*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,758 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 (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: HMBS NM_000190.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 2.02
• Publications: 13 publications found

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: Genomics England PanelApp, ClinGen, Orphanet, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-119090212-C-T is Pathogenic according to our data. Variant chr11-119090212-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 1486.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

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.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HMBS	NM_000190.4	MANE Select	c.445C>T	p.Arg149*	stop_gained	Exon 8 of 14	NP_000181.2
	HMBS	NM_001425056.1		c.445C>T	p.Arg149*	stop_gained	Exon 8 of 14	NP_001411985.1
	HMBS	NM_001425057.1		c.427C>T	p.Arg143*	stop_gained	Exon 8 of 14	NP_001411986.1	A0A3F2YNY7

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HMBS	ENST00000652429.1	MANE Select	c.445C>T	p.Arg149*	stop_gained	Exon 8 of 14	ENSP00000498786.1	P08397-1
	HMBS	ENST00000392841.1	TSL:1	c.394C>T	p.Arg132*	stop_gained	Exon 8 of 14	ENSP00000376584.1	P08397-2
	HMBS	ENST00000545621.5	TSL:1	n.*340C>T		non_coding_transcript_exon	Exon 8 of 10	ENSP00000444849.1	F5H4X2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461758 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727194

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44722

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: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111888

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000258 Hom.: 0

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
2	-	-	Acute intermittent porphyria (2)
1	-	-	HMBS-related disorder (1)
1	-	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.60	D
BayesDel_noAF	Pathogenic	0.55
CADD	Pathogenic	35
DANN	Uncertain	1.0
Eigen	Uncertain	0.41
Eigen_PC	Uncertain	0.27
FATHMM_MKL	Uncertain	0.92	D
PhyloP100		2.0
Vest4		0.94
GERP RS		3.1
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		2.6
Mutation Taster		=0/200	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
Splicevardb		2.0
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

Other links and lift over

dbSNP: rs118204120; hg19: chr11-118960922;