1-119750815-C-T

Position:

chr1-119750815-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PS1_ModeratePM2PP3_Moderate

The NM_005518.4(HMGCS2):c.1514G>A(p.Arg505Gln) variant causes a missense change. The variant allele was found at a frequency of 0.0000149 in 1,612,952 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 Uncertain significance (★★). Another nucleotide change resulting in same amino acid change has been previously reported as Likely pathogenicin UniProt.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

HMGCS2
NM_005518.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 6.96

Variant links:

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PS1

Transcript NM_005518.4 (HMGCS2) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in UniProt

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.873

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
HMGCS2	NM_005518.4 linkuse as main transcript	c.1514G>A	p.Arg505Gln	missense_variant	9/10	ENST00000369406.8	NP_005509.1
HMGCS2	NM_001166107.1 linkuse as main transcript	c.1388G>A	p.Arg463Gln	missense_variant	8/9		NP_001159579.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
HMGCS2	ENST00000369406.8 linkuse as main transcript	c.1514G>A	p.Arg505Gln	missense_variant	9/10	1	NM_005518.4	ENSP00000358414	P1	P54868-1
HMGCS2	ENST00000544913.2 linkuse as main transcript	c.1388G>A	p.Arg463Gln	missense_variant	8/9	2		ENSP00000439495		P54868-2

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152074

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

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

GnomAD3 exomes

AF:

0.0000159

AC:

AN:

251292

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135810

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000579

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000176

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000144

AC:

AN:

1460878

Hom.:

Cov.:

AF XY:

0.0000151

AC XY:

AN XY:

726818

show subpopulations

Gnomad4 AFR exome

AF:

0.000120

Gnomad4 AMR exome

AF:

0.0000671

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000117

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152074

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74270

show subpopulations

Gnomad4 AFR

AF:

0.0000483

Gnomad4 AMR

AF:

0.0000655

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000251

Hom.:

Bravo

AF:

0.0000113

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jul 16, 2024

Variant summary: HMGCS2 c.1514G>A (p.Arg505Gln) results in a conservative amino acid change located in the Hydroxymethylglutaryl-coenzyme A synthase, C-terminal domain (IPR013746) of the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 1.6e-05 in 251292 control chromosomes. c.1514G>A has been reported in the literature in homozygous or compound heterozygous individuals affected with 3-hydroxy-3-methylglutaryl-CoA synthase deficiency (Puisac_2018, Pitt_2015). These data indicate that the variant may be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in approximately 70% of normal HMG-CoA synthase activity when expressed in E. coli (Puisac_2018). The following publications have been ascertained in the context of this evaluation (PMID: 29597274, 25511235). ClinVar contains an entry for this variant (Variation ID: 2186499). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

3-hydroxy-3-methylglutaryl-CoA synthase deficiency

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 17, 2022

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 505 of the HMGCS2 protein (p.Arg505Gln). This variant is present in population databases (rs758519315, gnomAD 0.006%). This missense change has been observed in individuals with HMG-CoA synthase-2 deficiency (PMID: 25511235, 29597274). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). Experimental studies have shown that this missense change affects HMGCS2 function (PMID: 29597274). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.15

BayesDel_addAF

Benign

-0.055

BayesDel_noAF

Benign

-0.14

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.72

D;.

Eigen

Uncertain

0.42

Eigen_PC

Uncertain

0.37

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Pathogenic

0.98

D;D

M_CAP

Pathogenic

0.47

MetaRNN

Pathogenic

0.87

D;D

MetaSVM

Benign

-0.30

MutationAssessor

Uncertain

2.1

M;.

MutationTaster

Benign

1.0

D;D

PrimateAI

Benign

0.40

PROVEAN

Uncertain

-2.7

D;D

REVEL

Uncertain

0.52

Sift

Benign

0.087

T;T

Sift4G

Benign

0.12

T;T

Polyphen

1.0

D;.

Vest4

0.71

MVP

0.85

MPC

0.55

ClinPred

0.95

GERP RS

4.4

Varity_R

0.28

gMVP

0.55

Splicing

Name

Calibrated prediction

Score

Prediction

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over