7-97852329-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_001673.5(ASNS):c.1616C>T(p.Pro539Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000118 in 1,613,990 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: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000012 (0 hom.)
• Consequence: ASNS NM_001673.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 9.33

Genes affected

ASNS (HGNC:753): (asparagine synthetase (glutamine-hydrolyzing)) The protein encoded by this gene is involved in the synthesis of asparagine. This gene complements a mutation in the temperature-sensitive hamster mutant ts11, which blocks progression through the G1 phase of the cell cycle at nonpermissive temperature. Alternatively spliced transcript variants have been described for this gene. [provided by RefSeq, May 2010]

CZ1P-ASNS (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.865

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ASNS	NM_001673.5	c.1616C>T	p.Pro539Leu	missense_variant	13/13	ENST00000394308.8
CZ1P-ASNS	NR_147989.1	n.3319C>T		non_coding_transcript_exon_variant	19/19

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ASNS	ENST00000394308.8	c.1616C>T	p.Pro539Leu	missense_variant	13/13	1	NM_001673.5	P1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152132 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.0000123 AC: 18 AN: 1461858 Hom.: 0 Cov.: 31 AF XY: 0.0000151 AC XY: 11 AN XY: 727236

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: 0.0000144

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152132 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74306

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

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	Invitae	Apr 26, 2022	This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 539 of the ASNS protein (p.Pro539Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with ASNS-related conditions. ClinVar contains an entry for this variant (Variation ID: 453130). 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) performed at Invitae indicates that this missense variant is expected to disrupt ASNS 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Nov 08, 2017	The P539L variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. The P539L variant is not observed in large population cohorts (Lek et al., 2016). The P539L variant is a semi-conservative amino acid substitution, which may impact secondary protein structure as these residues differ in some properties. In silico analyses, including protein predictors and evolutionary conservation, support a deleterious effect. Based on the currently available information, it is unclear whether this variant is a pathogenic variant or a rare benign variant. -

Congenital microcephaly - severe encephalopathy - progressive cerebral atrophy syndrome Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Natera, Inc.

Sep 16, 2020

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.15
Cadd	Pathogenic	31
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.79	D;D;.;D;.;.;.
Eigen	Pathogenic	0.99
Eigen_PC	Pathogenic	0.92
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.97	D;.;.;.;.;D;D
M_CAP	Uncertain	0.13	D
MetaRNN	Pathogenic	0.86	D;D;D;D;D;D;D
MetaSVM	Uncertain	-0.047	T
MutationAssessor	Pathogenic	3.7	H;H;.;H;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.63	T
PROVEAN	Pathogenic	-8.5	D;D;D;D;D;D;D
REVEL	Pathogenic	0.70
Sift	Pathogenic	0.0	D;D;D;D;D;D;D
Sift4G	Uncertain	0.0020	D;D;D;D;D;D;D
Polyphen		1.0	D;D;.;D;.;.;.
Vest4		0.82
MutPred		0.54		Gain of catalytic residue at P539 (P = 0.005);Gain of catalytic residue at P539 (P = 0.005);.;Gain of catalytic residue at P539 (P = 0.005);.;.;.;
MVP		0.86
MPC		1.3
ClinPred		1.0	D
GERP RS		5.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.84
gMVP		0.88

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: rs1182799813; hg19: chr7-97481641;