17-31225204-G-T

Position:

• chr17-31225204-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_001042492.3(NF1):​c.1955G>T​(p.Arg652Leu) 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 (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: NF1 NM_001042492.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.43

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 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), NF1. . Gene score misZ 6.5427 (greater than the threshold 3.09). Trascript score misZ 8.4054 (greater than threshold 3.09). GenCC has associacion of gene with 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=0.42324647).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NF1	NM_001042492.3	c.1955G>T	p.Arg652Leu	missense_variant	17/58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.3	c.1955G>T	p.Arg652Leu	missense_variant	17/57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.1955G>T	p.Arg652Leu	missense_variant	17/58	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

Neurofibromatosis, type 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 21, 2020

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 tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. 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. This variant has been observed in individual(s) with breast cancer (PMID: 30287823). This variant is not present in population databases (ExAC no frequency). This sequence change replaces arginine with leucine at codon 652 of the NF1 protein (p.Arg652Leu). The arginine residue is moderately conserved and there is a moderate physicochemical difference between arginine and leucine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Uncertain	0.11	D
BayesDel_noAF	Uncertain	-0.080
CADD	Benign	21
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.50	T;.;T
Eigen	Uncertain	0.21
Eigen_PC	Uncertain	0.23
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Benign	0.81	T;T;T
M_CAP	Benign	0.058	D
MetaRNN	Benign	0.42	T;T;T
MetaSVM	Benign	-0.99	T
MutationAssessor	Benign	0.69	N;N;.
PrimateAI	Benign	0.48	T
PROVEAN	Benign	-1.1	N;N;N
REVEL	Benign	0.26
Sift	Uncertain	0.0090	D;D;D
Sift4G	Benign	0.064	T;T;T
Polyphen		0.87	P;P;.
Vest4		0.71
MutPred		0.44		Loss of solvent accessibility (P = 0.001);Loss of solvent accessibility (P = 0.001);.;
MVP		0.80
MPC		0.86
ClinPred		0.83	D
GERP RS		5.3
Varity_R		0.14
gMVP		0.34

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs587778549; hg19: chr17-29552222;