17-31219030-C-T

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 1P and 5B. PP2BP4_StrongBS2_Supporting

The NM_001042492.3(NF1):​c.1553C>T​(p.Thr518Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,613,506 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

NF1
NM_001042492.3 missense

Scores

3
16

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:1

Conservation

PhyloP100: 3.10
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

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.
BP4
Computational evidence support a benign effect (MetaRNN=0.046343803).
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 rank MANE Protein UniProt
NF1NM_001042492.3 linkc.1553C>T p.Thr518Ile missense_variant Exon 14 of 58 ENST00000358273.9 NP_001035957.1 P21359-1
NF1NM_000267.3 linkc.1553C>T p.Thr518Ile missense_variant Exon 14 of 57 NP_000258.1 P21359-2
NF1NM_001128147.3 linkc.1553C>T p.Thr518Ile missense_variant Exon 14 of 15 NP_001121619.1 P21359-5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NF1ENST00000358273.9 linkc.1553C>T p.Thr518Ile missense_variant Exon 14 of 58 1 NM_001042492.3 ENSP00000351015.4 P21359-1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152074
Hom.:
0
Cov.:
32
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:
0.000192
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000797
AC:
2
AN:
250798
Hom.:
0
AF XY:
0.00000738
AC XY:
1
AN XY:
135536
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000328
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000881
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461432
Hom.:
0
Cov.:
33
AF XY:
0.00000413
AC XY:
3
AN XY:
726988
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
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:
0.00000360
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152074
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74290
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000192
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Neurofibromatosis, type 1 Uncertain:1Benign:1
Sep 25, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Mar 15, 2022
Genome-Nilou Lab
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not specified Uncertain:1
Jun 04, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: NF1 c.1553C>T (p.Thr518Ile) results in a non-conservative amino acid change in the encoded protein sequence. Two of four in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 8e-06 in 250798 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.1553C>T in individuals affected with Neurofibromatosis Type 1 and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 142755). Based on the evidence outlined above, the variant was classified as uncertain significance. -

not provided Uncertain:1
May 05, 2021
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

In silico analysis supports that this missense variant does not alter protein structure/function; Observed in a male control unaffected by cancer (Momozawa 2018); This variant is associated with the following publications: (PMID: 30287823) -

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype Uncertain:1
Nov 03, 2020
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The c.1553C>T (p.T518I) alteration is located in exon 14 (coding exon 14) of the NF1 gene. This alteration results from a C to T substitution at nucleotide position 1553, causing the threonine (T) at amino acid position 518 to be replaced by an isoleucine (I). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Hereditary cancer-predisposing syndrome Uncertain:1
Feb 05, 2015
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The p.T518I variant (also known as c.1553C>T), located in coding exon 14 of the NF1 gene, results from a C to T substitution at nucleotide position 1553. The threonine at codon 518 is replaced by isoleucine, 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. To date, this alteration has been detected with an allele frequency of approximately 0.007% (greater than 30000 alleles tested) in our clinical cohort. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of p.T518I remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.28
BayesDel_addAF
Benign
-0.31
T
BayesDel_noAF
Benign
-0.58
CADD
Benign
19
DANN
Benign
0.11
DEOGEN2
Benign
0.37
.;T;.;.;T
Eigen
Benign
-0.49
Eigen_PC
Benign
-0.16
FATHMM_MKL
Uncertain
0.86
D
LIST_S2
Uncertain
0.92
D;D;D;D;D
M_CAP
Benign
0.053
D
MetaRNN
Benign
0.046
T;T;T;T;T
MetaSVM
Benign
-0.90
T
MutationAssessor
Benign
-1.7
N;N;N;N;.
PrimateAI
Uncertain
0.72
T
PROVEAN
Benign
0.24
.;N;N;N;N
REVEL
Benign
0.14
Sift
Benign
1.0
.;T;T;T;T
Sift4G
Benign
1.0
.;T;T;T;T
Polyphen
0.0
B;B;B;.;.
Vest4
0.21, 0.22, 0.16
MutPred
0.38
Loss of phosphorylation at T518 (P = 0.0151);Loss of phosphorylation at T518 (P = 0.0151);Loss of phosphorylation at T518 (P = 0.0151);Loss of phosphorylation at T518 (P = 0.0151);.;
MVP
0.22
MPC
0.74
ClinPred
0.15
T
GERP RS
5.7
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.065
gMVP
0.15

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.

Other links and lift over

dbSNP: rs587782696; hg19: chr17-29546048; API