17-31360593-T-C

Variant names:

• chr17-31360593-T-C
• rs1555537241
• NM_001042492.3:c.8267T>C

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001042492.3(NF1):​c.8267T>C​(p.Leu2756Pro) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign 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. L2756Q) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: NF1 NM_001042492.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.83
• Publications: 0 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: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.21411142).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF1	NM_001042492.3	c.8267T>C	p.Leu2756Pro	missense_variant	Exon 57 of 58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.4	c.8204T>C	p.Leu2735Pro	missense_variant	Exon 56 of 57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.8267T>C	p.Leu2756Pro	missense_variant	Exon 57 of 58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Jan 27, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.L2735P variant (also known as c.8204T>C), located in coding exon 56 of the NF1 gene, results from a T to C substitution at nucleotide position 8204. The leucine at codon 2735 is replaced by proline, an amino acid with similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. 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	Benign	0.11
BayesDel_addAF	Benign	-0.10	T
BayesDel_noAF	Benign	-0.38
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Benign	0.40	T;.;T
Eigen	Uncertain	0.27
Eigen_PC	Uncertain	0.39
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Uncertain	0.93	D;D;D
M_CAP	Uncertain	0.11	D
MetaRNN	Benign	0.21	T;T;T
MetaSVM	Benign	-0.99	T
MutationAssessor	Benign	0.0	N;.;.
PhyloP100		5.8
PrimateAI	Uncertain	0.72	T
PROVEAN	Benign	-0.73	N;N;N
REVEL	Benign	0.11
Sift	Benign	0.31	T;T;T
Sift4G	Benign	0.36	T;T;T
Polyphen		0.91	P;P;.
Vest4		0.49
MutPred		0.28		Gain of relative solvent accessibility (P = 0.0023);.;.;
MVP		0.33
MPC		1.0
ClinPred		0.86	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.33
gMVP		0.55
Mutation Taster		=42/58	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

Other links and lift over

dbSNP: rs1555537241; hg19: chr17-29687611;