1-23808231-T-A

Variant names:

• chr1-23808231-T-A
• NM_000191.3:c.654A>T
• HMGCL p.Leu218Leu

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000191.3(HMGCL):​c.654A>T​(p.Leu218Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. L218L) has been classified as Benign.

• Frequency:
  • Genomes: 𝑓 0.0 (0 hom., cov: 31)
  • Failed GnomAD Quality Control
• Consequence: HMGCL NM_000191.3 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.23
• Publications: 0 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: Myriad Women's Health, ClinGen, Orphanet, G2P, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

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.654A>T	p.Leu218Leu	synonymous	Exon 7 of 9	NP_000182.2	P35914-1
	HMGCL	NM_001166059.2		c.441A>T	p.Leu147Leu	synonymous	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.654A>T	p.Leu218Leu	synonymous	Exon 7 of 9	ENSP00000363614.3	P35914-1
	HMGCL	ENST00000509389.5	TSL:1	n.361-16A>T		intron	N/A
	HMGCL	ENST00000892104.1		c.654A>T	p.Leu218Leu	synonymous	Exon 7 of 10	ENSP00000562163.1

Frequencies

GnomAD3 genomes AF: 0.00 AC: 0 AN: 152078 Hom.: 0 Cov.: 31

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 47

GnomAD4 genome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 152078 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 74280

African (AFR) AF: 0.00 AC: 0 AN: 41406

American (AMR) AF: 0.00 AC: 0 AN: 15264

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5164

South Asian (SAS) AF: 0.00 AC: 0 AN: 4832

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: 0.00 AC: 0 AN: 68012

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

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.34
CADD	Benign	14
DANN	Benign	0.74
PhyloP100		1.2
Mutation Taster		=92/8	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.27		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.27		Position offset: -16

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr1-24134721;