NM_005518.4:c.1270C>A

Variant names:

• chr1-119753304-G-T
• rs137852637
• NM_005518.4:c.1270C>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_005518.4(HMGCS2):​c.1270C>A​(p.Arg424Arg) 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.

• Frequency: Genomes: not found (cov: 32)
• Consequence: HMGCS2 NM_005518.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.985
• Publications: 0 publications found

Genes affected

HMGCS2 (HGNC:5008): (3-hydroxy-3-methylglutaryl-CoA synthase 2) The protein encoded by this gene belongs to the HMG-CoA synthase family. It is a mitochondrial enzyme that catalyzes the first reaction of ketogenesis, a metabolic pathway that provides lipid-derived energy for various organs during times of carbohydrate deprivation, such as fasting. Mutations in this gene are associated with HMG-CoA synthase deficiency. Alternatively spliced transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Oct 2009]

HMGCS2 Gene-Disease associations (from GenCC):

• 3-hydroxy-3-methylglutaryl-CoA synthase deficiency

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia, Orphanet, ClinGen, G2P

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.59).
• BP7: Synonymous conserved (PhyloP=0.985 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
HMGCS2	NM_005518.4	c.1270C>A	p.Arg424Arg	synonymous_variant	Exon 7 of 10	ENST00000369406.8	NP_005509.1
HMGCS2	NM_001166107.1	c.1144C>A	p.Arg382Arg	synonymous_variant	Exon 6 of 9		NP_001159579.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HMGCS2	ENST00000369406.8	c.1270C>A	p.Arg424Arg	synonymous_variant	Exon 7 of 10	1	NM_005518.4	ENSP00000358414.3
HMGCS2	ENST00000544913.2	c.1144C>A	p.Arg382Arg	synonymous_variant	Exon 6 of 9	2		ENSP00000439495.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.59
CADD	Benign	9.6
DANN	Benign	0.60
PhyloP100		0.98
Mutation Taster		=100/0	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: rs137852637; hg19: chr1-120295927;