rs567317952

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2BP4_StrongBS1_Supporting

The NM_024537.4(CARS2):c.101C>G(p.Ala34Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000004 in 1,500,078 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

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

Exomes 𝑓: 0.0000022 ( 0 hom. )

Consequence

CARS2
NM_024537.4 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 0.811

Variant links:

Genes affected

CARS2 (HGNC:25695): (cysteinyl-tRNA synthetase 2, mitochondrial) This gene encodes a putative member of the class I family of aminoacyl-tRNA synthetases. These enzymes play a critical role in protein biosynthesis by charging tRNAs with their cognate amino acids. This protein is encoded by the nuclear genome but is likely to be imported to the mitochondrion where it is thought to catalyze the ligation of cysteine to tRNA molecules. A splice-site mutation in this gene has been associated with a novel progressive myoclonic epilepsy disease with similar symptoms to MERRF syndrome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jun 2017]

CARS2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.051053315).

BS1

Variant frequency is greater than expected in population eas. gnomad4 allele frequency = 0.0000198 (3/151642) while in subpopulation EAS AF= 0.000583 (3/5148). AF 95% confidence interval is 0.000159. There are 0 homozygotes in gnomad4. There are 1 alleles in male gnomad4 subpopulation. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CARS2	NM_024537.4 linkuse as main transcript	c.101C>G	p.Ala34Gly	missense_variant	1/15	ENST00000257347.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CARS2	ENST00000257347.9 linkuse as main transcript	c.101C>G	p.Ala34Gly	missense_variant	1/15	1	NM_024537.4	P1

Frequencies

GnomAD3 genomes

AF:

0.0000198

AC:

AN:

151534

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000581

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

AF:

0.00000222

AC:

AN:

1348436

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

665444

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000932

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000198

AC:

AN:

151642

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74126

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000583

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000189

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Combined oxidative phosphorylation defect type 27

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jul 25, 2022

This sequence change replaces alanine, which is neutral and non-polar, with glycine, which is neutral and non-polar, at codon 34 of the CARS2 protein (p.Ala34Gly). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with CARS2-related conditions. ClinVar contains an entry for this variant (Variation ID: 475611). 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: "Possibly Damaging"; Align-GVGD: "Class C0"). 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. -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 11, 2022

The c.101C>G (p.A34G) alteration is located in exon 1 (coding exon 1) of the CARS2 gene. This alteration results from a C to G substitution at nucleotide position 101, causing the alanine (A) at amino acid position 34 to be replaced by a glycine (G). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.069

BayesDel_addAF

Benign

-0.18

BayesDel_noAF

Benign

-0.50

Cadd

Benign

Dann

Benign

0.94

DEOGEN2

Benign

0.17

Eigen

Benign

-1.1

Eigen_PC

Benign

-1.2

FATHMM_MKL

Benign

0.050

LIST_S2

Benign

0.58

M_CAP

Benign

0.011

MetaRNN

Benign

0.051

MetaSVM

Benign

-1.0

MutationAssessor

Benign

1.6

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.67

PROVEAN

Benign

-1.5

REVEL

Benign

0.021

Sift

Benign

0.11

Sift4G

Benign

0.26

Polyphen

0.0060

Vest4

0.13

MutPred

0.31

Gain of catalytic residue at A34 (P = 0.0575);

MVP

0.24

MPC

2.6

ClinPred

0.12

GERP RS

-1.4

Varity_R

0.071

gMVP

0.35

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