rs143389605

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM1PP5

The NM_020320.5(RARS2):​c.442A>G​(p.Thr148Ala) variant causes a missense change. The variant allele was found at a frequency of 0.000574 in 1,613,050 control chromosomes in the GnomAD database, including 1 homozygotes. 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. T148S) has been classified as Uncertain significance.

Frequency

Genomes: š‘“ 0.00039 ( 0 hom., cov: 32)
Exomes š‘“: 0.00059 ( 1 hom. )

Consequence

RARS2
NM_020320.5 missense

Scores

3
9
7

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:5U:8

Conservation

PhyloP100: 4.58

Publications

3 publications found
Variant links:
Genes affected
RARS2 (HGNC:21406): (arginyl-tRNA synthetase 2, mitochondrial) This nuclear gene encodes a protein that localizes to the mitochondria, where it catalyzes the transfer of L-arginine to its cognate tRNA, an important step in translation of mitochondrially-encoded proteins. Defects in this gene are a cause of pontocerebellar hypoplasia type 6 (PCH6). Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2016]
RARS2 Gene-Disease associations (from GenCC):
  • mitochondrial disease
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • pontocerebellar hypoplasia type 6
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics, PanelApp Australia
  • complex neurodevelopmental disorder
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_020320.5
PP5
Variant 6-87548600-T-C is Pathogenic according to our data. Variant chr6-87548600-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 358237.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
RARS2NM_020320.5 linkc.442A>G p.Thr148Ala missense_variant Exon 6 of 20 ENST00000369536.10 NP_064716.2 Q5T160

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
RARS2ENST00000369536.10 linkc.442A>G p.Thr148Ala missense_variant Exon 6 of 20 1 NM_020320.5 ENSP00000358549.5 Q5T160

Frequencies

GnomAD3 genomes
AF:
0.000388
AC:
59
AN:
152228
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
Gnomad ASJ
AF:
0.00230
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000414
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000632
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.000548
AC:
137
AN:
250070
AF XY:
0.000547
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000116
Gnomad ASJ exome
AF:
0.00130
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000932
Gnomad NFE exome
AF:
0.000858
Gnomad OTH exome
AF:
0.000657
GnomAD4 exome
AF:
0.000594
AC:
867
AN:
1460704
Hom.:
1
Cov.:
30
AF XY:
0.000549
AC XY:
399
AN XY:
726652
show subpopulations
African (AFR)
AF:
0.0000598
AC:
2
AN:
33454
American (AMR)
AF:
0.000157
AC:
7
AN:
44672
Ashkenazi Jewish (ASJ)
AF:
0.00165
AC:
43
AN:
26084
East Asian (EAS)
AF:
0.0000253
AC:
1
AN:
39558
South Asian (SAS)
AF:
0.000696
AC:
60
AN:
86170
European-Finnish (FIN)
AF:
0.0000752
AC:
4
AN:
53204
Middle Eastern (MID)
AF:
0.000175
AC:
1
AN:
5730
European-Non Finnish (NFE)
AF:
0.000650
AC:
722
AN:
1111482
Other (OTH)
AF:
0.000447
AC:
27
AN:
60350
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.464
Heterozygous variant carriers
0
41
82
122
163
204
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
28
56
84
112
140
<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:
0.000387
AC:
59
AN:
152346
Hom.:
0
Cov.:
32
AF XY:
0.000322
AC XY:
24
AN XY:
74496
show subpopulations
African (AFR)
AF:
0.0000722
AC:
3
AN:
41580
American (AMR)
AF:
0.000131
AC:
2
AN:
15304
Ashkenazi Jewish (ASJ)
AF:
0.00230
AC:
8
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.000414
AC:
2
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000632
AC:
43
AN:
68034
Other (OTH)
AF:
0.000473
AC:
1
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
5
10
15
20
25
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:
0.000615
Hom.:
6
Bravo
AF:
0.000400
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000814
AC:
7
ExAC
AF:
0.000626
AC:
76
Asia WGS
AF:
0.000577
AC:
2
AN:
3478
EpiCase
AF:
0.000327
EpiControl
AF:
0.000712

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:5Uncertain:8
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Pathogenic:3Uncertain:5
Jul 07, 2023
Clinical Genetics Laboratory, Skane University Hospital Lund
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

May 15, 2025
GeneDx
Significance:Likely pathogenic
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: 31014978, 30634555, 33972171, 29977174, 35468344, 24123792, 40025839) -

Jun 03, 2024
Greenwood Genetic Center Diagnostic Laboratories, Greenwood Genetic Center
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

PM3_Very Strong, PP3 -

Aug 20, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with alanine, which is neutral and non-polar, at codon 148 of the RARS2 protein (p.Thr148Ala). This variant is present in population databases (rs143389605, gnomAD 0.1%), and has an allele count higher than expected for a pathogenic variant. This missense change has been observed in individual(s) with clinical features of pontocerebellar hypoplasia (PMID: 24123792, 30634555). ClinVar contains an entry for this variant (Variation ID: 358237). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. 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. -

-
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Sep 01, 2021
CeGaT Center for Human Genetics Tuebingen
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Genome Diagnostics Laboratory, Amsterdam University Medical Center
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Pontocerebellar hypoplasia type 6 Pathogenic:2Uncertain:2
Sep 16, 2020
Natera, Inc.
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

-
Baylor Genetics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Feb 10, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: RARS2 c.442A>G (p.Thr148Ala) results in a non-conservative amino acid change located in the Arginyl-tRNA synthetase, catalytic core domain of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.00055 in 250070 control chromosomes. This frequency is not significantly higher than estimated for a pathogenic variant in RARS2 causing Pontocerebellar Hypoplasia, Type 6 (0.00055 vs 0.0011), allowing no conclusion about variant significance. c.442A>G has been reported in the literature in an individual affected with psychomotor retardation, autism and ataxia and in another individual with delayed development, brain atrophy, pontecerebellar atropy (Neveling_2013, Roux_2021). Both patients are reported to be carrying a pathogenic second variant in RARS2. A third patient has been reported in the literature with a second allele of uncertain signfiicance who had ataxia (Jou_2019). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 33972171, 24123792, 34717047, 30634555). ClinVar contains an entry for this variant (Variation ID: 358237). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.31
BayesDel_addAF
Benign
-0.10
T
BayesDel_noAF
Uncertain
0.0
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Benign
0.24
T
Eigen
Uncertain
0.57
Eigen_PC
Uncertain
0.54
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Uncertain
0.90
D
M_CAP
Benign
0.045
D
MetaRNN
Uncertain
0.45
T
MetaSVM
Benign
-0.44
T
MutationAssessor
Benign
1.8
L
PhyloP100
4.6
PrimateAI
Uncertain
0.75
T
PROVEAN
Pathogenic
-4.9
D
REVEL
Uncertain
0.56
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
0.99
D
Vest4
0.82
MVP
0.82
MPC
0.50
ClinPred
0.29
T
GERP RS
4.4
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.6
Varity_R
0.87
gMVP
0.87
Mutation Taster
=32/68
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs143389605; hg19: chr6-88258318; COSMIC: COSV101057306; API