rs797045306

Positions:

• chr7-97864333-T-A
• chr7-97864333-T-G

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM2 PM5 PP3_Strong PP5

The ENST00000394308.8(ASNS):​c.413A>T​(p.Asp138Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,474 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D138A) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: ASNS ENST00000394308.8 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 7.21

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 Likely_pathogenic. Variant got 9 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-97864333-T-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1332874.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.986
• PP5: Variant 7-97864333-T-A is Pathogenic according to our data. Variant chr7-97864333-T-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 210338.We mark this variant Likely_pathogenic, oryginal submissions are: {Pathogenic=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ASNS	NM_001673.5	c.413A>T	p.Asp138Val	missense_variant	4/13	ENST00000394308.8	NP_001664.3
CZ1P-ASNS	NR_147989.1	n.2042A>T		non_coding_transcript_exon_variant	10/19

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ASNS	ENST00000394308.8	c.413A>T	p.Asp138Val	missense_variant	4/13	1	NM_001673.5	ENSP00000377845	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461474 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727050

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

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

Pathogenic, criteria provided, single submitter

clinical testing

Genetic Services Laboratory, University of Chicago

Apr 10, 2015

- -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 01, 2021

This sequence change replaces aspartic acid with valine at codon 138 of the ASNS protein (p.Asp138Val). The aspartic acid residue is highly conserved and there is a large physicochemical difference between aspartic acid and valine. This variant is not present in population databases (ExAC 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: 210338). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.47
CADD	Pathogenic	28
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.87	D;D;.;D;.;.;.;D;.
Eigen	Pathogenic	0.95
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Pathogenic	0.98	D;.;.;.;.;D;D;D;D
M_CAP	Pathogenic	0.59	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.2	H;H;.;H;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.65	T
PROVEAN	Pathogenic	-8.8	D;D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.93
Sift	Pathogenic	0.0	D;D;D;D;D;D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D;D;D;.;.
Polyphen		1.0	D;D;.;D;.;.;.;.;.
Vest4		0.99
MutPred		0.86		Loss of catalytic residue at D138 (P = 0.0326);Loss of catalytic residue at D138 (P = 0.0326);.;Loss of catalytic residue at D138 (P = 0.0326);.;.;.;Loss of catalytic residue at D138 (P = 0.0326);Loss of catalytic residue at D138 (P = 0.0326);
MVP		0.98
MPC		1.5
ClinPred		1.0	D
GERP RS		4.2
RBP_binding_hub_radar		1.0
RBP_regulation_power_radar		2.8
Varity_R		0.99
gMVP		0.97

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: rs797045306; hg19: chr7-97493645;