3-49100194-A-G

Variant names:

• chr3-49100194-A-G
• rs899079673
• NM_005051.3:c.1160T>C

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_005051.3(QARS1):​c.1160T>C​(p.Phe387Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,876 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. F387C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: QARS1 NM_005051.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.67
• Publications: 0 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: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.947

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.1160T>C	p.Phe387Ser	missense	Exon 13 of 24	NP_005042.1
	QARS1	NM_001272073.2		c.1127T>C	p.Phe376Ser	missense	Exon 13 of 24	NP_001259002.1
	QARS1	NR_073590.2		n.1135T>C		non_coding_transcript_exon	Exon 13 of 24

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	QARS1	ENST00000306125.12	TSL:1 MANE Select	c.1160T>C	p.Phe387Ser	missense	Exon 13 of 24	ENSP00000307567.6
	QARS1	ENST00000464962.6	TSL:1	c.725T>C	p.Phe242Ser	missense	Exon 12 of 23	ENSP00000489011.1
	QARS1	ENST00000414533.5	TSL:2	c.1127T>C	p.Phe376Ser	missense	Exon 13 of 24	ENSP00000390015.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251066 AF XY: 0.00000737

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461876 Hom.: 0 Cov.: 35 AF XY: 0.00000138 AC XY: 1 AN XY: 727238

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: 26134

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

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: 0.00 AC: 0 AN: 1111996

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

GnomAD4 genome Cov.: 33

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

Jul 10, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces phenylalanine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 387 of the QARS protein (p.Phe387Ser). This variant is present in population databases (no rsID available, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with QARS-related conditions. ClinVar contains an entry for this variant (Variation ID: 2001375). 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 QARS protein function. 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.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Pathogenic	0.19
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.93	D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Benign	0.067	D
MetaRNN	Pathogenic	0.95	D
MetaSVM	Uncertain	0.083	D
MutationAssessor	Pathogenic	4.6	H
PhyloP100		8.7
PrimateAI	Uncertain	0.65	T
PROVEAN	Pathogenic	-7.5	D
REVEL	Pathogenic	0.71
Sift	Uncertain	0.0010	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.79		Gain of disorder (P = 0.0183)
MVP		0.72
MPC		1.4
ClinPred		1.0	D
GERP RS		6.1
PromoterAI		-0.0091	Neutral
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		2.7
Varity_R		0.99
gMVP		0.94
Mutation Taster		=38/62	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: rs899079673; hg19: chr3-49137627;