chr9-98056840-G-T

Variant names:

• chr9-98056840-G-T
• NM_018946.4:c.32G>T

Variant summary

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

The NM_018946.4(NANS):​c.32G>T​(p.Arg11Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 34)
• Consequence: NANS NM_018946.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.30

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 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.895

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NANS	NM_018946.4	c.32G>T	p.Arg11Leu	missense_variant	Exon 1 of 6	ENST00000210444.6	NP_061819.2
TRIM14	XM_047424162.1	c.*29-21027C>A		intron_variant	Intron 6 of 6		XP_047280118.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NANS	ENST00000210444.6	c.32G>T	p.Arg11Leu	missense_variant	Exon 1 of 6	1	NM_018946.4	ENSP00000210444.5
NANS	ENST00000480925.1	n.71G>T		non_coding_transcript_exon_variant	Exon 1 of 2	2
NANS	ENST00000495319.1	n.73G>T		non_coding_transcript_exon_variant	Exon 1 of 5	3

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome Cov.: 42

GnomAD4 genome Cov.: 34

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

May 19, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. This variant has not been reported in the literature in individuals affected with NANS-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 11 of the NANS protein (p.Arg11Leu). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.48
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.080
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Benign	0.031	T
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.91	D
M_CAP	Uncertain	0.22	D
MetaRNN	Pathogenic	0.90	D
MetaSVM	Benign	-0.61	T
MutationAssessor	Uncertain	2.7	M
PrimateAI	Uncertain	0.77	T
PROVEAN	Uncertain	-2.9	D
REVEL	Uncertain	0.43
Sift	Uncertain	0.018	D
Sift4G	Uncertain	0.011	D
Polyphen		0.99	D
Vest4		0.76
MutPred		0.75		Gain of sheet (P = 0.0827);
MVP		0.82
MPC		0.86
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.69
gMVP		0.85

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr9-100819122;