rs756594937

Variant names:

• chr16-70268336-G-A
• rs756594937
• NM_001605.3:c.1006C>T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM1 PM2

The NM_001605.3(AARS1):​c.1006C>T​(p.His336Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,848 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. H336R) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: AARS1 NM_001605.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.13
• Publications: 0 publications found

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]

AARS1 Gene-Disease associations (from GenCC):

• Charcot-Marie-Tooth disease axonal type 2N

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), Orphanet
• undetermined early-onset epileptic encephalopathy

  Inheritance: AR, AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Illumina, Orphanet
• developmental and epileptic encephalopathy, 29

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• trichothiodystrophy 8, nonphotosensitive

  Inheritance: AR, Unknown Classification: LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 8 uncertain in NM_001605.3
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
AARS1	NM_001605.3	c.1006C>T	p.His336Tyr	missense_variant	Exon 8 of 21	ENST00000261772.13	NP_001596.2
AARS1	XM_047433666.1	c.1006C>T	p.His336Tyr	missense_variant	Exon 8 of 16		XP_047289622.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
AARS1	ENST00000261772.13	c.1006C>T	p.His336Tyr	missense_variant	Exon 8 of 21	1	NM_001605.3	ENSP00000261772.8

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251480 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: 0.0000544

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461848 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727222

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

American (AMR) AF: 0.0000224 AC: 1 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39694

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

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

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

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111984

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Charcot-Marie-Tooth disease type 2 Uncertain:1

Apr 10, 2016

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces histidine with tyrosine at codon 336 of the AARS protein (p.His336Tyr). The histidine residue is moderately conserved and there is a moderate physicochemical difference between histidine and tyrosine. This variant is present in population databases (rs756594937, ExAC 0.01%) but has not been reported in the literature in individuals with a AARS-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). In summary, this variant is a rare missense change with uncertain impact on protein function. There is no indication that it causes disease, but the available evidence is currently insufficient to prove that conclusively. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Benign	0.0063	T
BayesDel_noAF	Uncertain	-0.060
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Benign	0.20	T
Eigen	Uncertain	0.38
Eigen_PC	Uncertain	0.52
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D
M_CAP	Benign	0.035	D
MetaRNN	Uncertain	0.73	D
MetaSVM	Benign	-0.95	T
MutationAssessor	Benign	0.48	N
PhyloP100		8.1
PrimateAI	Uncertain	0.79	T
PROVEAN	Benign	-0.51	N
REVEL	Benign	0.21
Sift	Uncertain	0.011	D
Sift4G	Uncertain	0.014	D
Polyphen		0.94	P
Vest4		0.74
MutPred		0.48		Loss of methylation at R333 (P = 0.1048);
MVP		0.79
MPC		0.72
ClinPred		0.58	D
GERP RS		5.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.2
Varity_R		0.64
gMVP		0.81
Mutation Taster		=43/57	disease causing

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

Other links and lift over

dbSNP: rs756594937; hg19: chr16-70302239;