rs199474730

Positions:

• chr17-31227547-T-A
• chr17-31227547-T-C

Variant summary

Our verdict is Pathogenic. Variant got 17 ACMG points: 17P and 0B. PS1 PM1 PM2 PM5 PP2 PP3_Strong PP5_Moderate

The NM_001042492.3(NF1):​c.2350T>A​(p.Trp784Arg) variant causes a missense 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. Variant has been reported in ClinVar as Likely pathogenic (★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Pathogenic in Lovd. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. W784C) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: NF1 NM_001042492.3 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.49

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 17 ACMG points.

• PS1: Transcript NM_001042492.3 (NF1) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in Lovd
• PM1: In a helix (size 21) in uniprot entity NF1_HUMAN there are 13 pathogenic changes around while only 0 benign (100%) in NM_001042492.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-31227549-G-C is described in Lovd as [Pathogenic].
• 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). The gene has 399 curated pathogenic missense variants (we use a threshold of 10). The gene has 143 curated benign missense variants. GenCC has associacion of the gene with neurofibromatosis, familial spinal, hereditary pheochromocytoma-paraganglioma, neurofibromatosis type 1, Watson syndrome, neurofibromatosis-Noonan syndrome, Moyamoya disease, familial ovarian cancer.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.984
• PP5: Variant 17-31227547-T-A is Pathogenic according to our data. Variant chr17-31227547-T-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 996401.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr17-31227547-T-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NF1	NM_001042492.3	c.2350T>A	p.Trp784Arg	missense_variant	20/58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.3	c.2350T>A	p.Trp784Arg	missense_variant	20/57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.2350T>A	p.Trp784Arg	missense_variant	20/58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neurofibromatosis, type 1 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Genome Diagnostics Laboratory, The Hospital for Sick Children

Oct 26, 2020

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.35	D
BayesDel_noAF	Pathogenic	0.27
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D;.;D
Eigen	Pathogenic	0.69
Eigen_PC	Uncertain	0.66
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D;D;D
M_CAP	Pathogenic	0.86	D
MetaRNN	Pathogenic	0.98	D;D;D
MetaSVM	Uncertain	-0.24	T
MutationAssessor	Uncertain	2.4	M;M;.
PrimateAI	Pathogenic	0.89	D
PROVEAN	Pathogenic	-11	D;D;D
REVEL	Pathogenic	0.80
Sift	Pathogenic	0.0	D;D;D
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	D;D;.
Vest4		0.98
MutPred		0.86		Gain of disorder (P = 0.0059);Gain of disorder (P = 0.0059);.;
MVP		0.91
MPC		2.3
ClinPred		1.0	D
GERP RS		4.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.93
gMVP		0.96

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

Publications

LitVar

Other links and lift over

dbSNP: rs199474730; hg19: chr17-29554565;