chr17-31343135-G-C

Variant names:

• chr17-31343135-G-C
• rs1135402900
• NM_001042492.3:c.7189G>C

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM2 PM5 PP2 PP3_Strong PP5_Moderate

The NM_001042492.3(NF1):​c.7189G>C​(p.Gly2397Arg) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 16/25 in silico tools predict a damaging outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G2397F?) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: NF1 NM_001042492.3 missense, splice_region
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.18

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 Pathogenic. Variant got 11 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-31343134-AGG-ATTTA is described in Lovd as [Pathogenic].
• 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.
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 17-31343135-G-C is Pathogenic according to our data. Variant chr17-31343135-G-C is described in ClinVar as [Pathogenic]. Clinvar id is 578365.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF1	NM_001042492.3	c.7189G>C	p.Gly2397Arg	missense_variant, splice_region_variant	Exon 48 of 58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.3	c.7126G>C	p.Gly2376Arg	missense_variant, splice_region_variant	Exon 47 of 57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.7189G>C	p.Gly2397Arg	missense_variant, splice_region_variant	Exon 48 of 58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neurofibromatosis, type 1 Pathogenic:1

Jan 20, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 2376 of the NF1 protein (p.Gly2376Arg). This variant also falls at the last nucleotide of exon 47, which is part of the consensus splice site for this exon. This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with clinical features of NF1-related conditions (PMID: 31776437; internal data). ClinVar contains an entry for this variant (Variation ID: 578365). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. This variant disrupts the c.7126G nucleotide in the NF1 gene. Other variant(s) that disrupt this nucleotide have been determined to be pathogenic (PMID: 26056819, 28961165, 30290804). This suggests that this nucleotide is clinically significant, and that variants that disrupt this position are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.16
CADD	Pathogenic	34
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.97	D;.;D
Eigen	Pathogenic	0.73
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.98	D;D;D
M_CAP	Pathogenic	0.92	D
MetaRNN	Pathogenic	0.91	D;D;D
MetaSVM	Uncertain	-0.065	T
MutationAssessor	Uncertain	2.2	M;.;.
PrimateAI	Pathogenic	0.88	D
PROVEAN	Pathogenic	-6.5	D;D;D
REVEL	Pathogenic	0.74
Sift	Uncertain	0.0010	D;D;D
Sift4G	Pathogenic	0.0010	D;D;D
Polyphen		0.73	P;D;.
Vest4		0.99
MutPred		0.72		Gain of solvent accessibility (P = 0.0055);.;.;
MVP		0.93
MPC		1.6
ClinPred		1.0	D
GERP RS		5.3
Varity_R		0.76
gMVP		0.96

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	1.0
SpliceAI score (max)		0.54		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.54		Position offset: 0

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

Publications

LitVar

Other links and lift over

dbSNP: rs1135402900; hg19: chr17-29670153;