3-49098008-T-G

Variant names:

• chr3-49098008-T-G
• rs142480574
• NM_005051.3:c.2261A>C

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_005051.3(QARS1):​c.2261A>C​(p.Asp754Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,890 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D754G) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: QARS1 NM_005051.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.54
• Publications: 4 publications found

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]

QARS1 Gene-Disease associations (from GenCC):

• diffuse cerebral and cerebellar atrophy - intractable seizures - progressive microcephaly syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, ClinGen, Orphanet
• microcephaly-short stature-intellectual disability-facial dysmorphism syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

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

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.805

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005051.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	QARS1	NM_005051.3	MANE Select	c.2261A>C	p.Asp754Ala	missense	Exon 23 of 24	NP_005042.1
	QARS1	NM_001272073.2		c.2228A>C	p.Asp743Ala	missense	Exon 23 of 24	NP_001259002.1
	QARS1	NR_073590.2		n.2236A>C		non_coding_transcript_exon	Exon 23 of 24

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	QARS1	ENST00000306125.12	TSL:1 MANE Select	c.2261A>C	p.Asp754Ala	missense	Exon 23 of 24	ENSP00000307567.6
	QARS1	ENST00000464962.6	TSL:1	c.1826A>C	p.Asp609Ala	missense	Exon 22 of 23	ENSP00000489011.1
	QARS1	ENST00000414533.5	TSL:2	c.2228A>C	p.Asp743Ala	missense	Exon 23 of 24	ENSP00000390015.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD2 exomes AF: 0.0000119 AC: 3 AN: 251484 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000163

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461890 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727246

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.0000756 AC: 3 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112010

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 31

ExAC AF: 0.0000247 AC: 3

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Aug 01, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.2261A>C (p.D754A) alteration is located in exon 23 (coding exon 23) of the QARS gene. This alteration results from a A to C substitution at nucleotide position 2261, causing the aspartic acid (D) at amino acid position 754 to be replaced by an alanine (A). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.39
BayesDel_addAF	Benign	-0.032	T
BayesDel_noAF	Uncertain	-0.020
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.42	T
Eigen	Pathogenic	0.88
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.90	D
M_CAP	Uncertain	0.16	D
MetaRNN	Pathogenic	0.81	D
MetaSVM	Benign	-0.58	T
MutationAssessor	Pathogenic	3.3	M
PhyloP100		7.5
PrimateAI	Uncertain	0.57	T
PROVEAN	Pathogenic	-7.3	D
REVEL	Uncertain	0.56
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0020	D
Polyphen		1.0	D
Vest4		0.86
MutPred		0.38		Loss of ubiquitination at K759 (P = 0.0304)
MVP		0.57
MPC		1.2
ClinPred		0.99	D
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.84
gMVP		0.68
Mutation Taster		=22/78	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs142480574; hg19: chr3-49135441;