17-31206243-G-A

Position:

chr17-31206243-G-A

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 1P and 3B. PP2BP4_ModerateBS2_Supporting

The ENST00000358273.9(NF1):c.1264G>A(p.Ala422Thr) variant causes a missense change. The variant allele was found at a frequency of 0.00000496 in 1,613,320 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. 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. A422S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

NF1
ENST00000358273.9 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:7

Conservation

PhyloP100: 7.05

Variant links:

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

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=0.25624102).

BS2

High AC in GnomAdExome4 at 7 AD gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein
NF1	NM_001042492.3 linkuse as main transcript	c.1264G>A	p.Ala422Thr	missense_variant	12/58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.3 linkuse as main transcript	c.1264G>A	p.Ala422Thr	missense_variant	12/57		NP_000258.1
NF1	NM_001128147.3 linkuse as main transcript	c.1264G>A	p.Ala422Thr	missense_variant	12/15		NP_001121619.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9 linkuse as main transcript	c.1264G>A	p.Ala422Thr	missense_variant	12/58	1	NM_001042492.3	ENSP00000351015	P1	P21359-1

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

152052

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000796

AC:

AN:

251378

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135860

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000578

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000479

AC:

AN:

1461268

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

726972

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000447

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000450

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000658

AC:

AN:

152052

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74266

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:7

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Neurofibromatosis, type 1

Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	St. Jude Molecular Pathology, St. Jude Children's Research Hospital	Jun 26, 2023	The NF1 c.1264G>A (p.Ala422Thr) missense change has a maximum subpopulation frequency of 0.0056% in gnomAD v2.1.1 (https://gnomad.broadinstitute.org/). The in silico tool REVEL is inconclusive about a pathogenic or benign effect of this variant on protein function, and to our knowledge functional studies have not been performed. This variant has been reported in one individual with primary MDS classified as refractory anemia with excess blasts (PMID: 29146900). To our knowledge, this variant has not been reported in individuals with Neurofibromatosis type 1. In summary, the evidence currently available is insufficient to determine the clinical significance of this variant. It has therefore been classified as of uncertain significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Dec 14, 2023	This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 422 of the NF1 protein (p.Ala422Thr). This variant is present in population databases (rs786202145, gnomAD 0.003%). This variant has not been reported in the literature in individuals affected with NF1-related conditions. ClinVar contains an entry for this variant (Variation ID: 185401). 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 with a negative predictive value of 95%. 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Mar 15, 2022	- -

Neurofibromatosis, type 1;C0349639:Juvenile myelomonocytic leukemia;C0553586:Café-au-lait macules with pulmonary stenosis;C1834235:Neurofibromatosis, familial spinal;C2931482:Neurofibromatosis-Noonan syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Feb 11, 2022

- -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jul 03, 2023

In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 24308032) -

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 20, 2020

The c.1264G>A (p.A422T) alteration is located in exon 12 (coding exon 12) of the NF1 gene. This alteration results from a G to A substitution at nucleotide position 1264, causing the alanine (A) at amino acid position 422 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Hereditary cancer-predisposing syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 29, 2015

The p.A422T variant (also known as c.1264G>A), located in coding exon 12 of the NF1 gene, results from a G to A substitution at nucleotide position 1264. The alanine at codon 422 is replaced by threonine, an amino acid with similar properties. This variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6503 samples (13006 alleles) with coverage at this position. To date, this alteration has been detected with an allele frequency of approximately 0.004% (greater than 110000 alleles tested) in our clinical cohort. This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of p.A422T remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.088

BayesDel_addAF

Benign

-0.0044

BayesDel_noAF

Benign

-0.16

CADD

Benign

DANN

Benign

0.13

DEOGEN2

Uncertain

0.51

.;D;.;.;T

Eigen

Benign

0.047

Eigen_PC

Uncertain

0.25

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Uncertain

0.97

D;D;D;D;D

M_CAP

Benign

0.078

MetaRNN

Benign

0.26

T;T;T;T;T

MetaSVM

Benign

-0.49

MutationAssessor

Benign

0.69

N;N;N;N;.

MutationTaster

Benign

1.0

D;D;D

PrimateAI

Uncertain

0.76

PROVEAN

Benign

-1.2

.;N;N;N;N

REVEL

Uncertain

0.32

Sift

Benign

1.0

.;T;T;T;T

Sift4G

Benign

0.28

.;T;T;T;T

Polyphen

0.055

B;B;D;.;.

Vest4

0.52, 0.51, 0.44

MutPred

0.43

Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);.;

MVP

0.65

MPC

0.74

ClinPred

0.33

GERP RS

6.2

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.11

gMVP

0.26

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over