17-31182670-G-A

Position:

chr17-31182670-G-A

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 0P and 13B. BP4_StrongBP6_Very_StrongBS2_Supporting

The NM_001042492.3(NF1):c.888+5G>A variant causes a splice donor 5th base, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000199 in 1,611,870 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000020 ( 0 hom. )

Consequence

NF1
NM_001042492.3 splice_donor_5th_base, intron

Scores

Splicing: ADA: 0.4906

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:5

Conservation

PhyloP100: 2.18

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 Benign. Variant got -13 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.036648124).

BP6

Variant 17-31182670-G-A is Benign according to our data. Variant chr17-31182670-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 141338.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BS2

High AC in GnomAdExome4 at 29 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	Effect	MANE	Protein
NF1	NM_001042492.3 linkuse as main transcript	c.888+5G>A	splice_donor_5th_base_variant, intron_variant	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.3 linkuse as main transcript	c.888+5G>A	splice_donor_5th_base_variant, intron_variant		NP_000258.1
NF1	NM_001128147.3 linkuse as main transcript	c.888+5G>A	splice_donor_5th_base_variant, intron_variant		NP_001121619.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9 linkuse as main transcript	c.888+5G>A		splice_donor_5th_base_variant, intron_variant		1	NM_001042492.3	ENSP00000351015	P1	P21359-1

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152146

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:

0.000578

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.0000564

AC:

AN:

248134

Hom.:

AF XY:

0.0000447

AC XY:

AN XY:

134196

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000711

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.000164

GnomAD4 exome

AF:

0.0000199

AC:

AN:

1459606

Hom.:

Cov.:

AF XY:

0.0000165

AC XY:

AN XY:

726070

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000530

Gnomad4 SAS exome

AF:

0.0000233

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.0000995

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152264

Hom.:

Cov.:

AF XY:

0.0000403

AC XY:

AN XY:

74458

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000386

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.000473

Bravo

AF:

0.0000264

ExAC

AF:

0.0000824

AC:

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Benign:1

Benign, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Apr 25, 2021

Variant summary: NF1 c.888+5G>A alters a conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. 4/4 computational tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 5.6e-05 in 248134 control chromosomes, predominantly at a frequency of 0.00071 within the East Asian subpopulation in the gnomAD database. The observed variant frequency within East Asian control individuals in the gnomAD database is approximately 3.4 fold of the estimated maximal expected allele frequency for a pathogenic variant in NF1 causing Neurofibromatosis Type 1 phenotype (0.00021), strongly suggesting that the variant is a benign polymorphism found primarily in populations of East Asian origin. To our knowledge, no occurrence of c.888+5G>A in individuals affected with Neurofibromatosis Type 1 and no experimental evidence demonstrating its impact on protein function have been reported. At-least one co-occurrence with another pathogenic variant has been observed at our laboratory (TP53 c.742C>T, p.Arg248Trp), providing supporting evidence for a benign role. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. One laboratory classified the variant as likely benign, and one laboratory classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as benign. -

Neurofibromatosis, type 1

Benign:1

Benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 31, 2024

- -

not provided

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Feb 19, 2020

- -

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 09, 2019

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Hereditary cancer-predisposing syndrome

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 08, 2015

Insufficient or Conflicting Evidence -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.39

CADD

Benign

DANN

Benign

0.67

FATHMM_MKL

Uncertain

0.93

LIST_S2

Benign

0.31

MetaRNN

Benign

0.037

MutationTaster

Benign

1.0

D;D;D

GERP RS

3.9

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.49

dbscSNV1_RF

Benign

0.54

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