3-49097999-T-C

Position:

• chr3-49097999-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_005051.3(QARS1):​c.2270A>G​(p.Gln757Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000041 in 1,461,878 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: QARS1 NM_005051.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.08

Genes affected

QARS1 (HGNC:9751): (glutaminyl-tRNA synthetase 1) Aminoacyl-tRNA synthetases catalyze the aminoacylation of tRNA by their cognate amino acid. Because of their central role in linking amino acids with nucleotide triplets contained in tRNAs, aminoacyl-tRNA synthetases are thought to be among the first proteins that appeared in evolution. In metazoans, 9 aminoacyl-tRNA synthetases specific for glutamine (gln), glutamic acid (glu), and 7 other amino acids are associated within a multienzyme complex. Although present in eukaryotes, glutaminyl-tRNA synthetase (QARS) is absent from many prokaryotes, mitochondria, and chloroplasts, in which Gln-tRNA(Gln) is formed by transamidation of the misacylated Glu-tRNA(Gln). Glutaminyl-tRNA synthetase belongs to the class-I aminoacyl-tRNA synthetase family. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2013]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.12017098).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
QARS1	NM_005051.3	c.2270A>G	p.Gln757Arg	missense_variant	23/24	ENST00000306125.12
QARS1	NM_001272073.2	c.2237A>G	p.Gln746Arg	missense_variant	23/24
QARS1	XM_017006965.3	c.2151+193A>G		intron_variant
QARS1	NR_073590.2	n.2245A>G		non_coding_transcript_exon_variant	23/24

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
QARS1	ENST00000306125.12	c.2270A>G	p.Gln757Arg	missense_variant	23/24	1	NM_005051.3	P1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251472 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135906

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: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000410 AC: 6 AN: 1461878 Hom.: 0 Cov.: 30 AF XY: 0.00000413 AC XY: 3 AN XY: 727244

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: 0.00000450

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 31

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Diffuse cerebral and cerebellar atrophy - intractable seizures - progressive microcephaly syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 18, 2021

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. 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 tolerated. This variant has not been reported in the literature in individuals affected with QARS-related conditions. This variant is present in population databases (no rsID available, gnomAD no frequency). This sequence change replaces glutamine, which is neutral and polar, with arginine, which is basic and polar, at codon 757 of the QARS protein (p.Gln757Arg). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.067
BayesDel_addAF	Benign	-0.30	T
BayesDel_noAF	Benign	-0.68
CADD	Benign	16
DANN	Benign	0.97
DEOGEN2	Benign	0.088	T;.;T
Eigen	Benign	-0.62
Eigen_PC	Benign	-0.49
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Uncertain	0.95	D;D;D
M_CAP	Benign	0.0071	T
MetaRNN	Benign	0.12	T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.42	N;.;.
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.31	T
PROVEAN	Benign	-0.78	N;N;.
REVEL	Benign	0.022
Sift	Benign	0.13	T;T;.
Sift4G	Benign	0.28	T;T;T
Polyphen		0.0	B;.;.
Vest4		0.31
MutPred		0.34		Loss of ubiquitination at K759 (P = 0.0318);.;.;
MVP		0.24
MPC		0.34
ClinPred		0.022	T
GERP RS		1.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.049
gMVP		0.25

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

LitVar

Other links and lift over

dbSNP: rs1426097729; hg19: chr3-49135432;