17-31330397-A-G

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1PM2PM5PP3

The NM_001042492.3(NF1):​c.5711A>G​(p.Asn1904Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,616 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N1904T) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

NF1
NM_001042492.3 missense

Scores

8
8
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts P:1U:2

Conservation

PhyloP100: 8.91

Publications

2 publications found
Variant links:
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]
NF1 Gene-Disease associations (from GenCC):
  • neurofibromatosis type 1
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, PanelApp Australia, G2P, Genomics England PanelApp
  • neurofibromatosis-Noonan syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp, PanelApp Australia
  • Moyamoya disease
    Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
  • hereditary pheochromocytoma-paraganglioma
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • familial ovarian cancer
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 20 uncertain in NM_001042492.3
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr17-31330397-A-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 803368.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.75

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
NF1NM_001042492.3 linkc.5711A>G p.Asn1904Ser missense_variant Exon 39 of 58 ENST00000358273.9 NP_001035957.1
NF1NM_000267.4 linkc.5648A>G p.Asn1883Ser missense_variant Exon 38 of 57 NP_000258.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NF1ENST00000358273.9 linkc.5711A>G p.Asn1904Ser missense_variant Exon 39 of 58 1 NM_001042492.3 ENSP00000351015.4

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251290
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461616
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727122
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39680
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86244
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111784
Other (OTH)
AF:
0.00
AC:
0
AN:
60390
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.00
Hom.:
0
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Pathogenic:1Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Neurofibromatosis, type 1 Pathogenic:1Uncertain:1
Oct 07, 2020
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant has been reported as de novo in an infant who also carried a de novo SOX9 variant (PMID: 27959697), therefore it is uncertain if the c.5648A>G NF1 variant is causative of disease in this individual. ClinVar contains an entry for this variant (Variation ID: 220757). This sequence change replaces asparagine with serine at codon 1883 of the NF1 protein (p.Asn1883Ser). The asparagine residue is moderately conserved and there is a small physicochemical difference between asparagine and serine. This variant is not present in population databases (ExAC no frequency). 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: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site, but this prediction has not been confirmed by published transcriptional studies. 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.

May 01, 2016
Baylor Genetics
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

Our laboratory reported two molecular diagnoses in NF1 (NM_000267.3:c.5648A>G) and SOX9 (NM_000346.3:c.1427T>C) in an individual with Pierre Robin Sequence, dysmorphic features, atrial septal defect with patent ductus arteriosus, hypertrophic cardiomyopathy, multiple cafe au lait spots, deep creases to palms and soles, a history of prematurity and a perinatal course complicated by anhydramnios, preterm premature rupture of membranes, pre-eclampsia and respiratory failure.

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype Uncertain:1
Jun 19, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.N1883S variant (also known as c.5648A>G), located in coding exon 38 of the NF1 gene, results from an A to G substitution at nucleotide position 5648. The asparagine at codon 1883 is replaced by serine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this variant remains unclear.

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.48
BayesDel_addAF
Uncertain
0.13
D
BayesDel_noAF
Uncertain
-0.060
CADD
Uncertain
26
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.84
D;.;T;.
Eigen
Uncertain
0.52
Eigen_PC
Uncertain
0.59
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.96
D;D;D;D
M_CAP
Pathogenic
0.86
D
MetaRNN
Pathogenic
0.75
D;D;D;D
MetaSVM
Pathogenic
0.90
D
MutationAssessor
Benign
1.3
L;.;.;.
PhyloP100
8.9
PrimateAI
Pathogenic
0.82
D
PROVEAN
Uncertain
-4.2
D;D;D;.
REVEL
Pathogenic
0.71
Sift
Benign
0.035
D;D;D;.
Sift4G
Pathogenic
0.0
D;D;D;.
Vest4
0.75
ClinPred
0.96
D
GERP RS
5.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.36
gMVP
0.74
Mutation Taster
=2/98
disease causing

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

Other links and lift over

dbSNP: rs864622647; hg19: chr17-29657415; COSMIC: COSV100648144; API