17-31201151-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP2

The NM_001042492.3(NF1):c.1177C>T(p.His393Tyr) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,794 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. H393D) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: NF1 NM_001042492.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.61

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 Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, NF1

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NF1	NM_001042492.3	c.1177C>T	p.His393Tyr	missense_variant	10/58	ENST00000358273.9
NF1	NM_000267.3	c.1177C>T	p.His393Tyr	missense_variant	10/57
NF1	NM_001128147.3	c.1177C>T	p.His393Tyr	missense_variant	10/15

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NF1	ENST00000358273.9	c.1177C>T	p.His393Tyr	missense_variant	10/58	1	NM_001042492.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461794 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727188

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

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

Invitae

Jul 17, 2021

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. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt NF1 protein function. This variant has not been reported in the literature in individuals with NF1-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces histidine with tyrosine at codon 393 of the NF1 protein (p.His393Tyr). The histidine residue is highly conserved and there is a moderate physicochemical difference between histidine and tyrosine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Pathogenic	0.26	D
BayesDel_noAF	Uncertain	0.13
Cadd	Uncertain	24
Dann	Benign	0.70
Eigen	Benign	0.072
Eigen_PC	Benign	0.21
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.91	D;D;D;D;D
M_CAP	Pathogenic	0.43	D
MetaRNN	Uncertain	0.49	T;T;T;T;T
MetaSVM	Benign	-0.29	T
MutationAssessor	Benign	1.4	L;L;L;L;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.86	D
Polyphen		0.58	P;B;P;.;.
Vest4		0.32, 0.33, 0.41
MutPred		0.32		Gain of catalytic residue at H393 (P = 0.0674);Gain of catalytic residue at H393 (P = 0.0674);Gain of catalytic residue at H393 (P = 0.0674);Gain of catalytic residue at H393 (P = 0.0674);.;
MVP		0.86
MPC		0.80
ClinPred		0.89	D
GERP RS		5.3
Varity_R		0.23
gMVP		0.81

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr17-29528169;