17-31235772-G-T

Variant names:

• chr17-31235772-G-T
• rs1555615497
• NM_001042492.3:c.3870G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_001042492.3(NF1):​c.3870G>T​(p.Lys1290Asn) 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. 3/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K1290E) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: NF1 NM_001042492.3 missense, splice_region
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 9.41
• 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: Likely_pathogenic. The variant received 8 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, 15 uncertain in NM_001042492.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF1	NM_001042492.3	c.3870G>T	p.Lys1290Asn	missense_variant, splice_region_variant	Exon 28 of 58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.4	c.3870G>T	p.Lys1290Asn	missense_variant, splice_region_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.3870G>T	p.Lys1290Asn	missense_variant, splice_region_variant	Exon 28 of 58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.24	D
BayesDel_noAF	Uncertain	0.11
CADD	Pathogenic	35
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.89	D;.;T
Eigen	Pathogenic	0.91
Eigen_PC	Pathogenic	0.93
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.95	D;D;D
M_CAP	Pathogenic	0.63	D
MetaRNN	Pathogenic	0.82	D;D;D
MetaSVM	Uncertain	0.51	D
MutationAssessor	Uncertain	2.7	M;M;.
PhyloP100		9.4
PrimateAI	Pathogenic	0.90	D
PROVEAN	Uncertain	-3.9	D;D;D
REVEL	Uncertain	0.63
Sift	Benign	0.079	T;T;T
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	D;D;.
Vest4		0.95
MutPred		0.56		Loss of methylation at K1290 (P = 0.0113);Loss of methylation at K1290 (P = 0.0113);.;
MVP		0.88
MPC		1.7
ClinPred		0.99	D
GERP RS		6.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.82
gMVP		0.75
Mutation Taster		=2/98	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.97
SpliceAI score (max)		0.59		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.23		Position offset: -26
DS_DL_spliceai		0.59		Position offset: 0

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

Other links and lift over

dbSNP: rs1555615497; hg19: chr17-29562790;