rs202060864

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 1P and 1B. PP5BP4

The NM_006567.5(FARS2):​c.667C>T​(p.Arg223Cys) variant causes a missense change. The variant allele was found at a frequency of 0.000156 in 1,610,822 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R223P) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00015 ( 0 hom. )

Consequence

FARS2
NM_006567.5 missense

Scores

5
8
6

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:3

Conservation

PhyloP100: 3.61

Publications

7 publications found
Variant links:
Genes affected
FARS2 (HGNC:21062): (phenylalanyl-tRNA synthetase 2, mitochondrial) This gene encodes a protein that transfers phenylalanine to its cognate tRNA. This protein localizes to the mitochondrion and plays a role in mitochondrial protein translation. Mutations in this gene can cause combined oxidative phosphorylation deficiency 14 (Alpers encephalopathy). Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2016]
FARS2 Gene-Disease associations (from GenCC):
  • metabolic disease
    Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
  • combined oxidative phosphorylation defect type 14
    Inheritance: AR Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • hereditary spastic paraplegia 77
    Inheritance: AR Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • Leigh syndrome
    Inheritance: AR Classification: MODERATE Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PP5
Variant 6-5404596-C-T is Pathogenic according to our data. Variant chr6-5404596-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 214330.
BP4
Computational evidence support a benign effect (MetaRNN=0.26804993). . Strength limited to SUPPORTING due to the PP5.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FARS2NM_006567.5 linkc.667C>T p.Arg223Cys missense_variant Exon 3 of 7 ENST00000274680.9 NP_006558.1 O95363

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FARS2ENST00000274680.9 linkc.667C>T p.Arg223Cys missense_variant Exon 3 of 7 1 NM_006567.5 ENSP00000274680.4 O95363
FARS2ENST00000324331.10 linkc.667C>T p.Arg223Cys missense_variant Exon 3 of 7 1 ENSP00000316335.5 O95363
FARS2ENST00000445533.1 linkc.55C>T p.Arg19Cys missense_variant Exon 1 of 3 3 ENSP00000392525.1 Q5JRF7
FARS2ENST00000648580.1 linkn.667C>T non_coding_transcript_exon_variant Exon 3 of 9 ENSP00000497889.1 A0A3B3ITR6

Frequencies

GnomAD3 genomes
AF:
0.000256
AC:
39
AN:
152156
Hom.:
0
Cov.:
32
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:
0.00236
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000191
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000264
AC:
66
AN:
250050
AF XY:
0.000244
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.000994
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00208
Gnomad NFE exome
AF:
0.0000970
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000145
AC:
212
AN:
1458666
Hom.:
0
Cov.:
30
AF XY:
0.000139
AC XY:
101
AN XY:
725502
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33420
American (AMR)
AF:
0.00
AC:
0
AN:
44546
Ashkenazi Jewish (ASJ)
AF:
0.000767
AC:
20
AN:
26078
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39666
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85472
European-Finnish (FIN)
AF:
0.00165
AC:
88
AN:
53330
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5720
European-Non Finnish (NFE)
AF:
0.0000793
AC:
88
AN:
1110170
Other (OTH)
AF:
0.000249
AC:
15
AN:
60264
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.478
Heterozygous variant carriers
0
12
24
35
47
59
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000256
AC:
39
AN:
152156
Hom.:
0
Cov.:
32
AF XY:
0.000404
AC XY:
30
AN XY:
74308
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41426
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:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00236
AC:
25
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000191
AC:
13
AN:
68044
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.467
Heterozygous variant carriers
0
2
4
6
8
10
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000400
Hom.:
35
Bravo
AF:
0.000110
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.000148
AC:
18

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Combined oxidative phosphorylation defect type 14 Pathogenic:1Uncertain:1
Apr 10, 2018
Génétique des Maladies du Développement, Hospices Civils de Lyon
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 27, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 223 of the FARS2 protein (p.Arg223Cys). This variant is present in population databases (rs202060864, gnomAD 0.2%). This missense change has been observed in individual(s) with epileptic encephalopathy (PMID: 32597768). ClinVar contains an entry for this variant (Variation ID: 214330). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt FARS2 protein function with a positive predictive value of 95%. 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 Uncertain:2
Dec 26, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 32597768) -

-
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The FARS2 p.Arg223Cys variant was not identified in the literature nor was it identified in LOVD 3.0. The variant was identified in dbSNP (ID: rs202060864), ClinVar (classified as likely pathogenic by GeneDx and uncertain significance by Invitae. The variant was identified in control databases in 76 of 281418 chromosomes at a frequency of 0.0002701 (Genome Aggregation Database March 6, 2019, v2.1.1). The variant was observed in the following populations: European (Finnish) in 47 of 25106 chromosomes (freq: 0.001872), Ashkenazi Jewish in 10 of 10350 chromosomes (freq: 0.000966), European (non-Finnish) in 17 of 128836 chromosomes (freq: 0.000132) and African in 2 of 24928 chromosomes (freq: 0.00008), but was not observed in the Latino, East Asian, Other or South Asian populations. The p.Arg223 residue is conserved in mammals but not in more distantly related organisms, and four out of five computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) suggest that the variant may impact the protein; however, this information is not predictive enough to assume pathogenicity. The variant occurs outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.25
BayesDel_addAF
Benign
0.0026
T
BayesDel_noAF
Uncertain
0.070
CADD
Pathogenic
31
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.38
T;T;T
Eigen
Pathogenic
0.77
Eigen_PC
Pathogenic
0.71
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Uncertain
0.96
.;D;D
M_CAP
Benign
0.070
D
MetaRNN
Benign
0.27
T;T;T
MetaSVM
Uncertain
-0.076
T
MutationAssessor
Pathogenic
3.6
H;H;.
PhyloP100
3.6
PrimateAI
Uncertain
0.54
T
PROVEAN
Pathogenic
-4.9
D;D;D
REVEL
Uncertain
0.46
Sift
Uncertain
0.011
D;D;D
Sift4G
Uncertain
0.0030
D;D;D
Polyphen
1.0
D;D;.
Vest4
0.82
MVP
0.88
MPC
0.78
ClinPred
0.97
D
GERP RS
5.3
PromoterAI
-0.041
Neutral
Varity_R
0.56
gMVP
0.70
Mutation Taster
=50/50
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs202060864; hg19: chr6-5404829; COSMIC: COSV51178761; API