1-23808187-T-C

Variant names:

• chr1-23808187-T-C
• rs727503963
• NM_000191.3:c.698A>G

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PS3 PM2 PP2 PP3_Strong PP5_Very_Strong

The NM_000191.3(HMGCL):​c.698A>G​(p.His233Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000508 in 1,613,934 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 (★★). ClinVar reports functional evidence for this variant: "SCV002504205: Published functional studies demonstrate a damaging effect as this variant is associated with less than 1% 3-hydroxy-3-methylglutaryl-CoA lyase activity compared to wild-type (Roberts et al., 1996)" and additional evidence is available in ClinVar. Synonymous variant affecting the same amino acid position (i.e. H233H) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000046 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000051 (0 hom.)
• Consequence: HMGCL NM_000191.3 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:10
• Conservation: PhyloP100: 7.95
• Publications: 5 publications found

Genes affected

HMGCL (HGNC:5005): (3-hydroxy-3-methylglutaryl-CoA lyase) The protein encoded by this gene belongs to the HMG-CoA lyase family. It is a mitochondrial enzyme that catalyzes the final step of leucine degradation and plays a key role in ketone body formation. Mutations in this gene are associated with HMG-CoA lyase deficiency. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2009]

HMGCL Gene-Disease associations (from GenCC):

• 3-hydroxy-3-methylglutaric aciduria

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Myriad Women’s Health, Labcorp Genetics (formerly Invitae), ClinGen, G2P

ACMG classification

Our verdict: Pathogenic. The variant received 19 ACMG points.

• PS3: PS3 evidence extracted from ClinVar submissions: SCV002504205: Published functional studies demonstrate a damaging effect as this variant is associated with less than 1% 3-hydroxy-3-methylglutaryl-CoA lyase activity compared to wild-type (Roberts et al., 1996);; SCV000818257: Experimental studies have shown that this missense change affects HMGCL function (PMID: 8798725, 16330550).; SCV000919521: The most pronounced variant effect results in undetectable enzyme activity in the fibroblasts and lymphocytes of patients (Roberts_1996, Pospisilova_2003). PMID: 9784232, 19177531, 8798725, 14518825, 16330550
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 11 curated pathogenic missense variants (we use a threshold of 10). The gene has 2 curated benign missense variants. Gene score misZ: 0.46042 (below the threshold of 3.09). Trascript score misZ: 0.32928 (below the threshold of 3.09). GenCC associations: The gene is linked to 3-hydroxy-3-methylglutaric aciduria.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.992
• PP5: Variant 1-23808187-T-C is Pathogenic according to our data. Variant chr1-23808187-T-C is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 167180.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000191.3. 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
	HMGCL	NM_000191.3	MANE Select	c.698A>G	p.His233Arg	missense	Exon 7 of 9	NP_000182.2	P35914-1
	HMGCL	NM_001166059.2		c.485A>G	p.His162Arg	missense	Exon 5 of 7	NP_001159531.1	P35914-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HMGCL	ENST00000374490.8	TSL:1 MANE Select	c.698A>G	p.His233Arg	missense	Exon 7 of 9	ENSP00000363614.3	P35914-1
	HMGCL	ENST00000509389.5	TSL:1	n.389A>G		non_coding_transcript_exon	Exon 5 of 6
	HMGCL	ENST00000892104.1		c.698A>G	p.His233Arg	missense	Exon 7 of 10	ENSP00000562163.1

Frequencies

GnomAD3 genomes AF: 0.0000460 AC: 7 AN: 152108 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

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: 0.000103

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251412 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000513 AC: 75 AN: 1461826 Hom.: 0 Cov.: 31 AF XY: 0.0000481 AC XY: 35 AN XY: 727208

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: 26134

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: 53380

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

European-Non Finnish (NFE) AF: 0.0000638 AC: 71 AN: 1111990

Other (OTH) AF: 0.0000662 AC: 4 AN: 60392

GnomAD4 genome AF: 0.0000460 AC: 7 AN: 152108 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74312

African (AFR) AF: 0.00 AC: 0 AN: 41390

American (AMR) AF: 0.00 AC: 0 AN: 15274

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5190

South Asian (SAS) AF: 0.00 AC: 0 AN: 4824

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10610

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.000103 AC: 7 AN: 68030

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.0000602 Hom.: 0

Bravo AF: 0.0000529

TwinsUK AF: 0.000539 AC: 2

ALSPAC AF: 0.000259 AC: 1

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

ClinVar submissions

Significance: Pathogenic/Likely pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
6	-	-	Deficiency of hydroxymethylglutaryl-CoA lyase (6)
2	-	-	not provided (2)
1	-	-	HMGCL-related disorder (1)
1	-	-	Long chain 3-hydroxyacyl-CoA dehydrogenase deficiency (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.86
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.60
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.99	D
Eigen	Pathogenic	0.76
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.44	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.81	D
MutationAssessor	Pathogenic	4.8	H
PhyloP100		7.9
PrimateAI	Uncertain	0.72	T
PROVEAN	Pathogenic	-7.7	D
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.99
MutPred		0.99		Loss of catalytic residue at C234 (P = 0.0559)
MVP		0.99
MPC		0.53
ClinPred		1.0	D
GERP RS		5.7
Varity_R		0.99
gMVP		1.0
Mutation Taster		=2/98	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs727503963; hg19: chr1-24134677;