17-31248995-C-T

Variant names:

• chr17-31248995-C-T
• NM_001042492.3:c.3986C>T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 5P and 2B. PM1 PM2 PP2 BP4_Moderate

The NM_001042492.3(NF1):​c.3986C>T​(p.Ser1329Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,780 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 (★★). Synonymous variant affecting the same amino acid position (i.e. S1329S) has been classified as Benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: NF1 NM_001042492.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 2.20

Genes affected

NF1 (HGNC:7765): (neurofibromin 1) This gene product appears to function as a negative regulator of the ras signal transduction pathway. Mutations in this gene have been linked to neurofibromatosis type 1, juvenile myelomonocytic leukemia and Watson syndrome. The mRNA for this gene is subject to RNA editing (CGA>UGA->Arg1306Term) resulting in premature translation termination. Alternatively spliced transcript variants encoding different isoforms have also been described for this gene. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM1: In a domain Ras-GAP (size 216) in uniprot entity NF1_HUMAN there are 42 pathogenic changes around while only 3 benign (93%) in NM_001042492.3
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the NF1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 399 curated pathogenic missense variants (we use a threshold of 10). The gene has 143 curated benign missense variants. Gene score misZ: 6.5427 (above the threshold of 3.09). Trascript score misZ: 8.4054 (above the threshold of 3.09). GenCC associations: The gene is linked to neurofibromatosis, familial spinal, hereditary pheochromocytoma-paraganglioma, neurofibromatosis type 1, Watson syndrome, neurofibromatosis-Noonan syndrome, Moyamoya disease, familial ovarian cancer.
• BP4: Computational evidence support a benign effect (MetaRNN=0.2609771).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF1	NM_001042492.3	c.3986C>T	p.Ser1329Leu	missense_variant	Exon 30 of 58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.3	c.3986C>T	p.Ser1329Leu	missense_variant	Exon 30 of 57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.3986C>T	p.Ser1329Leu	missense_variant	Exon 30 of 58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461780 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727198

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: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Neurofibromatosis, type 1 Uncertain:1

Sep 30, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces serine, which is neutral and polar, with leucine, which is neutral and non-polar, at codon 1329 of the NF1 protein (p.Ser1329Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with NF1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1495315). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt NF1 protein function with a positive predictive value of 80%. 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. -

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype Uncertain:1

Apr 27, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.S1329L variant (also known as c.3986C>T), located in coding exon 30 of the NF1 gene, results from a C to T substitution at nucleotide position 3986. The serine at codon 1329 is replaced by leucine, an amino acid with dissimilar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.067
BayesDel_addAF	Benign	0.000036	T
BayesDel_noAF	Benign	-0.24
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.79	D;.;T
Eigen	Benign	0.075
Eigen_PC	Benign	0.20
FATHMM_MKL	Benign	0.42	N
LIST_S2	Uncertain	0.95	D;D;D
M_CAP	Uncertain	0.23	D
MetaRNN	Benign	0.26	T;T;T
MetaSVM	Uncertain	-0.094	T
MutationAssessor	Uncertain	2.0	M;M;.
PrimateAI	Uncertain	0.56	T
PROVEAN	Uncertain	-3.6	D;D;D
REVEL	Uncertain	0.33
Sift	Benign	0.13	T;T;T
Sift4G	Benign	0.075	T;T;T
Polyphen		0.039	B;B;.
Vest4		0.30
MutPred		0.43		Loss of phosphorylation at S1329 (P = 0.0285);Loss of phosphorylation at S1329 (P = 0.0285);.;
MVP		0.74
MPC		0.62
ClinPred		0.84	D
GERP RS		5.7
Varity_R		0.29
gMVP		0.16

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: chr17-29576013;