16-70269622-G-C

Position:

• chr16-70269622-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_001605.3(AARS1):​c.958C>G​(p.Arg320Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,664 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: AARS1 NM_001605.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 2.18

Genes affected

AARS1 (HGNC:20): (alanyl-tRNA synthetase 1) The human alanyl-tRNA synthetase (AARS) belongs to a family of tRNA synthases, of the class II enzymes. Class II tRNA synthases evolved early in evolution and are highly conserved. This is reflected by the fact that 498 of the 968-residue polypeptide human AARS shares 41% identity witht the E.coli protein. tRNA synthases are the enzymes that interpret the RNA code and attach specific aminoacids to the tRNAs that contain the cognate trinucleotide anticodons. They consist of a catalytic domain which interacts with the amino acid acceptor-T psi C helix of the tRNA, and a second domain which interacts with the rest of the tRNA structure. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a helix (size 20) in uniprot entity SYAC_HUMAN there are 7 pathogenic changes around while only 0 benign (100%) in NM_001605.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.983

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
AARS1	NM_001605.3	c.958C>G	p.Arg320Gly	missense_variant	7/21	ENST00000261772.13	NP_001596.2
AARS1	XM_047433666.1	c.958C>G	p.Arg320Gly	missense_variant	7/16		XP_047289622.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
AARS1	ENST00000261772.13	c.958C>G	p.Arg320Gly	missense_variant	7/21	1	NM_001605.3	ENSP00000261772	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251222 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135830

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: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461664 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 727170

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

Bravo AF: 0.00000756

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Oct 01, 2023	AARS1: PM2, PM5, PP3 -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Mar 29, 2024	Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 25817015) -

Charcot-Marie-Tooth disease type 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 25, 2023

This variant is present in population databases (rs138490305, gnomAD 0.0009%). This sequence change replaces arginine, which is basic and polar, with glycine, which is neutral and non-polar, at codon 320 of the AARS protein (p.Arg320Gly). 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. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on AARS protein function. ClinVar contains an entry for this variant (Variation ID: 543183). This variant has not been reported in the literature in individuals affected with AARS-related conditions. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.38	D
BayesDel_noAF	Pathogenic	0.31
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.84	D
Eigen	Uncertain	0.66
Eigen_PC	Uncertain	0.52
FATHMM_MKL	Uncertain	0.90	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.30	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Uncertain	0.63	D
MutationAssessor	Pathogenic	3.7	H
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.90	D
PROVEAN	Pathogenic	-6.5	D
REVEL	Pathogenic	0.81
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0030	D
Polyphen		1.0	D
Vest4		0.83
MutPred		0.87		Loss of methylation at R320 (P = 0.0259);
MVP		0.86
MPC		0.26
ClinPred		0.98	D
GERP RS		4.7
Varity_R		0.95
gMVP		0.95

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.18		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

Other links and lift over

dbSNP: rs138490305; hg19: chr16-70303525;