chr13-110683051-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP5

The NM_024537.4(CARS2):​c.655G>A​(p.Ala219Thr) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.0000144 in 1,598,120 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000015 ( 0 hom. )

Consequence

CARS2
NM_024537.4 missense, splice_region

Scores

1
1
17
Splicing: ADA: 0.9997
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4U:1

Conservation

PhyloP100: 4.94
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 13-110683051-C-T is Pathogenic according to our data. Variant chr13-110683051-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 180135.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Uncertain_significance=1}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
CARS2NM_024537.4 linkuse as main transcriptc.655G>A p.Ala219Thr missense_variant, splice_region_variant 6/15 ENST00000257347.9 NP_078813.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
CARS2ENST00000257347.9 linkuse as main transcriptc.655G>A p.Ala219Thr missense_variant, splice_region_variant 6/151 NM_024537.4 ENSP00000257347 P1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152234
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000127
AC:
3
AN:
236916
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
128670
show subpopulations
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 SAS exome
AF:
0.0000349
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000183
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000145
AC:
21
AN:
1445886
Hom.:
0
Cov.:
30
AF XY:
0.0000139
AC XY:
10
AN XY:
719326
show subpopulations
Gnomad4 AFR exome
AF:
0.0000310
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000595
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000108
Gnomad4 OTH exome
AF:
0.0000336
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152234
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74380
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000843
Hom.:
0
Bravo
AF:
0.0000227
ExAC
AF:
0.0000165
AC:
2

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:4Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Combined oxidative phosphorylation defect type 27 Pathogenic:3Uncertain:1
Likely pathogenic, no assertion criteria providedclinical testingRare Genetic Disease Lab, Dept of Zoology, Government Postgraduate College Dargai Malakand, Higher Education Govt. of Khyber PakhtunkhwaFeb 06, 2023- -
Pathogenic, no assertion criteria providedliterature onlyOMIMDec 02, 2014- -
Likely pathogenic, criteria provided, single submitterclinical testingNeuberg Centre For Genomic Medicine, NCGM-The missense c.655G>A p.Ala219Thr variant in CARS2 gene has been reported in homozygous state in multiple individuals affected with Combined oxidative phosphorylation deficiency 27 Kapoor D et al. 2021; Chen T et al. 2017; Hallmann K et al. 2014. The p.Ala219Thr variant has allele frequency 0.001% in gnomAD Exomes and is novel not in any individuals in 1000 Genomes. This variant has been reported to the ClinVar database as Uncertain Significance / Pathogenic / Likely pathogenic.The amino acid change p.Ala219Thr in CARS2 is predicted as conserved by GERP++ and PhyloP across 100 vertebrates. The amino acid Ala at position 219 is changed to a Thr changing protein sequence and it might alter its composition and physico-chemical properties. Functional studies are required to prove the pathogenicity for the variant, for these reasons, this variant has been classified as Likely Pathogenic. -
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpDec 11, 2023This sequence change affects codon 219 of the CARS2 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the CARS2 protein. RNA analysis indicates that this variant induces altered splicing and likely results in a shortened protein product. This variant is present in population databases (rs727505361, gnomAD 0.003%). This variant has been observed in individual(s) with CARS2-related conditions (PMID: 25361775, 34704010). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 180135). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Studies have shown that this variant results in skipping of exon 6, but is expected to preserve the integrity of the reading-frame (PMID: 25361775). 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. -
not provided Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingGeneDxFeb 12, 2024Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Messenger RNA studies show the variant leads to loss of exon 6 resulting in an in frame deletion of 28 amino acids belonging to a conserved surface loop of the cysteinyl-tRNA synthetase protein (PMID: 25361775); This variant is associated with the following publications: (PMID: 25361775, 37359369, 37151360, 34704010) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.067
BayesDel_addAF
Benign
-0.37
T
BayesDel_noAF
Benign
-0.66
CADD
Benign
22
DANN
Benign
0.93
DEOGEN2
Benign
0.13
T
Eigen
Benign
-0.095
Eigen_PC
Benign
0.096
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Benign
0.62
T
M_CAP
Pathogenic
0.40
D
MetaRNN
Benign
0.17
T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
0.015
N
MutationTaster
Benign
0.90
D
PrimateAI
Benign
0.38
T
PROVEAN
Benign
-0.83
N
REVEL
Benign
0.12
Sift
Benign
0.66
T
Sift4G
Benign
0.57
T
Polyphen
0.010
B
Vest4
0.097
MVP
0.47
MPC
0.16
ClinPred
0.48
T
GERP RS
5.4
Varity_R
0.11
gMVP
0.43

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.98
SpliceAI score (max)
0.92
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.92
Position offset: 0

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.

Other links and lift over

dbSNP: rs727505361; hg19: chr13-111335398; API