NM_020320.5:c.442A>G

Variant names:

Variant summary

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

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).

Frequency

Genomes: 𝑓 0.00039 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00059 ( 1 hom. )

Consequence

RARS2
NM_020320.5 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 4.58

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 links:

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 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 id is 358237.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=4, Uncertain_significance=5}. Variant chr6-87548600-T-C is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
RARS2	NM_020320.5 link	c.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
RARS2	ENST00000369536.10 link	c.442A>G	p.Thr148Ala	missense_variant	Exon 6 of 20	1	NM_020320.5	ENSP00000358549.5		Q5T160

Frequencies

GnomAD3 genomes

AF:

0.000388

AC:

AN:

152228

Hom.:

Cov.:

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

GnomAD3 exomes

AF:

0.000548

AC:

137

AN:

250070

Hom.:

AF XY:

0.000547

AC XY:

AN XY:

135214

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 SAS exome

AF:

0.000557

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.:

Cov.:

AF XY:

0.000549

AC XY:

399

AN XY:

726652

show subpopulations

Gnomad4 AFR exome

AF:

0.0000598

Gnomad4 AMR exome

AF:

0.000157

Gnomad4 ASJ exome

AF:

0.00165

Gnomad4 EAS exome

AF:

0.0000253

Gnomad4 SAS exome

AF:

0.000696

Gnomad4 FIN exome

AF:

0.0000752

Gnomad4 NFE exome

AF:

0.000650

Gnomad4 OTH exome

AF:

0.000447

GnomAD4 genome

AF:

0.000387

AC:

AN:

152346

Hom.:

Cov.:

AF XY:

0.000322

AC XY:

AN XY:

74496

show subpopulations

Gnomad4 AFR

AF:

0.0000722

Gnomad4 AMR

AF:

0.000131

Gnomad4 ASJ

AF:

0.00230

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000414

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000632

Gnomad4 OTH

AF:

0.000473

Alfa

AF:

0.000543

Hom.:

Bravo

AF:

0.000400

TwinsUK

AF:

0.000270

AC:

ALSPAC

AF:

0.000259

AC:

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000814

AC:

ExAC

AF:

0.000626

AC:

Asia WGS

AF:

0.000577

AC:

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

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

- -

Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Genome Diagnostics Laboratory, Amsterdam University Medical Center

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

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 -

Jul 07, 2023

Clinical Genetics Laboratory, Skane University Hospital Lund

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

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. -

Jan 17, 2024

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) -

Sep 01, 2021

CeGaT Center for Human Genetics Tuebingen

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

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

- -

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

- -

Oct 31, 2018

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

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

BayesDel_noAF

Uncertain

0.0

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Benign

0.24

Eigen

Uncertain

0.57

Eigen_PC

Uncertain

0.54

FATHMM_MKL

Uncertain

0.93

LIST_S2

Uncertain

0.90

M_CAP

Benign

0.045

MetaRNN

Uncertain

0.45

MetaSVM

Benign

-0.44

MutationAssessor

Benign

1.8

PrimateAI

Uncertain

0.75

PROVEAN

Pathogenic

-4.9

REVEL

Uncertain

0.56

Sift

Pathogenic

0.0

Sift4G

Pathogenic

0.0

Polyphen

0.99

Vest4

0.82

MVP

0.82

MPC

0.50

ClinPred

0.29

GERP RS

4.4

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.6

Varity_R

0.87

gMVP

0.87

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

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