17-31235769-C-T

Variant names:

• chr17-31235769-C-T
• rs138186428
• NM_001042492.3:c.3867C>T

Variant summary

Our verdict is Benign. The variant received -8 ACMG points: 0P and 8B. BP4_Moderate BP6 BP7 BS2

The NM_001042492.3(NF1):​c.3867C>T​(p.Phe1289Phe) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00131 in 1,614,010 control chromosomes in the GnomAD database, including 3 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.00088 (0 hom., cov: 31)
  • Exomes 𝑓: 0.0014 (3 hom.)
• Consequence: NF1 NM_001042492.3 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4 B:16
• Conservation: PhyloP100: 0.820
• Publications: 5 publications found

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

ACMG classification

Our verdict: Benign. The variant received -8 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.39).
• BP6: Variant 17-31235769-C-T is Benign according to our data. Variant chr17-31235769-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 184320.
• BP7: Synonymous conserved (PhyloP=0.82 with no splicing effect.
• BS2: High AC in GnomAd4 at 134 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF1	NM_001042492.3	c.3867C>T	p.Phe1289Phe	synonymous_variant	Exon 28 of 58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.4	c.3867C>T	p.Phe1289Phe	synonymous_variant	Exon 28 of 57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.3867C>T	p.Phe1289Phe	synonymous_variant	Exon 28 of 58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes AF: 0.000881 AC: 134 AN: 152144 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00111

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000828

Gnomad FIN AF: 0.000283

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00143

Gnomad OTH AF: 0.00143

GnomAD2 exomes AF: 0.00121 AC: 303 AN: 250978 AF XY: 0.00122

Gnomad AFR exome AF: 0.000185

Gnomad AMR exome AF: 0.000723

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.000464

Gnomad NFE exome AF: 0.00214

Gnomad OTH exome AF: 0.00147

GnomAD4 exome AF: 0.00135 AC: 1977 AN: 1461748 Hom.: 3 Cov.: 33 AF XY: 0.00137 AC XY: 999 AN XY: 727164

African (AFR) AF: 0.000269 AC: 9 AN: 33480

American (AMR) AF: 0.000693 AC: 31 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39686

South Asian (SAS) AF: 0.000580 AC: 50 AN: 86254

European-Finnish (FIN) AF: 0.000750 AC: 40 AN: 53324

Middle Eastern (MID) AF: 0.000347 AC: 2 AN: 5768

European-Non Finnish (NFE) AF: 0.00159 AC: 1766 AN: 1111984

Other (OTH) AF: 0.00131 AC: 79 AN: 60394

GnomAD4 genome AF: 0.000880 AC: 134 AN: 152262 Hom.: 0 Cov.: 31 AF XY: 0.000806 AC XY: 60 AN XY: 74448

African (AFR) AF: 0.000241 AC: 10 AN: 41558

American (AMR) AF: 0.00111 AC: 17 AN: 15286

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5180

South Asian (SAS) AF: 0.000829 AC: 4 AN: 4826

European-Finnish (FIN) AF: 0.000283 AC: 3 AN: 10602

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.00143 AC: 97 AN: 68018

Other (OTH) AF: 0.00142 AC: 3 AN: 2116

Alfa AF: 0.00133 Hom.: 0

Bravo AF: 0.000948

EpiCase AF: 0.00104

EpiControl AF: 0.00130

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4 Benign:16

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Benign:5

Mar 02, 2017

Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Oct 16, 2023

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jun 01, 2025

CeGaT Center for Human Genetics Tuebingen

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

NF1: BP4, BP7 -

Apr 26, 2021

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is associated with the following publications: (PMID: 18041031, 16944272, 16199547, 15060124) -

Aug 21, 2017

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: The NF1 c.3867C>T (p.Phe1289Phe) variant involves the alteration of a non-conserved nucleotide, resulting in a synonymous change located in the Rho GTPase activation protein domain (InterPro). One in silico tool predicts a damaging outcome for this variant. 5/5 splice prediction tools predict no significant impact on normal splicing. ESE finder predicts that this variant may affect the binding sites for splicing enhancers. However, these predictions have yet to be confirmed by functional studies. This variant was found in the large control database ExAC in 179/121342 control chromosomes (3 homozygotes) at a frequency of 0.0014752, which is approximately 7 times the estimated maximal expected allele frequency of a pathogenic NF1 variant (0.0002084), suggesting this variant is likely a benign polymorphism. This variant was found in Neurofibromatosis type 1 patients, including in one patient co-occurring with NF-1 c.1885G>A, p.G629R (not in our internal database, DM in HGMD) and was classified as a polymorphism (Mattocks_2004, Brinckmann_2007, Griffiths_2006). In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as likely benign/benign. Taken together, this variant is classified as benign. -

Neurofibromatosis, type 1 Uncertain:1 Benign:3

Jun 03, 2016

Clinical Molecular Genetics Laboratory, Johns Hopkins All Children's Hospital

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Nov 01, 2016

Center for Human Genetics, Inc, Center for Human Genetics, Inc

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Feb 03, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not specified Benign:3

Feb 05, 2021

Genetic Services Laboratory, University of Chicago

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mar 07, 2017

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

p.Phe1289Phe in exon 28 of NF1: This variant is not expected to have clinical si gnificance because it does not alter an amino acid residue and is not located wi thin the splice consensus sequence. It has been identified in 0.2% (156/66710) o f European chromosomes by the Exome Aggregation Consortium (ExAC, http://exac.br oadinstitute.org; dbSNP rs138186428). -

-

PreventionGenetics, part of Exact Sciences

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Benign:3

Jul 24, 2014

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Oct 07, 2020

Sema4, Sema4

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: curation

- -

Sep 27, 2022

Institute for Biomarker Research, Medical Diagnostic Laboratories, L.L.C.

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Neurofibromatosis-Noonan syndrome Uncertain:1

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Neurofibromatosis, familial spinal Uncertain:1

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Café-au-lait macules with pulmonary stenosis Uncertain:1

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Neurofibromatosis, type 1;C0349639:Juvenile myelomonocytic leukemia;C0553586:Café-au-lait macules with pulmonary stenosis;C1834235:Neurofibromatosis, familial spinal;C2931482:Neurofibromatosis-Noonan syndrome Benign:1

Aug 30, 2022

Department of Pathology and Laboratory Medicine, Sinai Health System

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

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

Jun 01, 2023

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.39
CADD	Benign	8.5
DANN	Benign	0.65
PhyloP100		0.82
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=100/0	polymorphism

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

Other links and lift over

dbSNP: rs138186428; hg19: chr17-29562787;