9-98078228-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_018946.4(NANS):c.484A>G(p.Met162Val) variant causes a missense change. The variant allele was found at a frequency of 0.0000142 in 1,614,042 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 31)
  • Exomes 𝑓: 0.000013 (0 hom.)
• Consequence: NANS NM_018946.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.88

Genes affected

NANS (HGNC:19237): (N-acetylneuraminate synthase) This gene encodes an enzyme that functions in the biosynthetic pathways of sialic acids. In vitro, the encoded protein uses N-acetylmannosamine 6-phosphate and mannose 6-phosphate as substrates to generate phosphorylated forms of N-acetylneuraminic acid (Neu5Ac) and 2-keto-3-deoxy-D-glycero-D-galacto-nononic acid (KDN), respectively; however, it exhibits much higher activity toward the Neu5Ac phosphate product. In insect cells, expression of this gene results in Neu5Ac and KDN production. This gene is related to the E. coli sialic acid synthase gene neuB, and it can partially restore sialic acid synthase activity in an E. coli neuB-negative mutant. [provided by RefSeq, Jul 2008]

TRIM14 (HGNC:16283): (tripartite motif containing 14) The protein encoded by this gene is a member of the tripartite motif (TRIM) family. The TRIM motif includes three zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. The protein localizes to cytoplasmic bodies and its function has not been determined. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Mar 2010]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.24551132).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NANS	NM_018946.4	c.484A>G	p.Met162Val	missense_variant	4/6	ENST00000210444.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NANS	ENST00000210444.6	c.484A>G	p.Met162Val	missense_variant	4/6	1	NM_018946.4	P1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152158 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000131

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000795 AC: 2 AN: 251496 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135922

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 SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000130 AC: 19 AN: 1461884 Hom.: 0 Cov.: 30 AF XY: 0.0000138 AC XY: 10 AN XY: 727242

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000504

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000144

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152158 Hom.: 0 Cov.: 31 AF XY: 0.0000269 AC XY: 2 AN XY: 74328

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.000131

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000547 Hom.: 0

Bravo AF: 0.0000151

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Mar 21, 2022

This sequence change replaces methionine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 162 of the NANS protein (p.Met162Val). This variant is present in population databases (no rsID available, gnomAD 0.005%). This variant has not been reported in the literature in individuals affected with NANS-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). 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	Benign	0.10
BayesDel_addAF	Benign	-0.14	T
BayesDel_noAF	Benign	-0.27
Cadd	Benign	23
Dann	Uncertain	0.99
DEOGEN2	Benign	0.0022	T;T
Eigen	Benign	0.15
Eigen_PC	Uncertain	0.29
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.92	D;D
M_CAP	Benign	0.017	T
MetaRNN	Benign	0.25	T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.5	L;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.50	T
PROVEAN	Benign	-1.9	N;N
REVEL	Benign	0.15
Sift	Benign	0.031	D;T
Sift4G	Uncertain	0.033	D;D
Polyphen		0.26	B;.
Vest4		0.79
MutPred		0.45		Gain of catalytic residue at M162 (P = 0.0619);.;
MVP		0.42
MPC		0.40
ClinPred		0.62	D
GERP RS		5.3
Varity_R		0.39
gMVP		0.77

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

Publications

LitVar

Other links and lift over

dbSNP: rs1359203722; hg19: chr9-100840510;