17-31350271-T-C

Position:

• chr17-31350271-T-C

Variant summary

Our verdict is Benign. Variant got -17 ACMG points: 0P and 17B. BP4_Strong BP6_Very_Strong BP7 BS2

The ENST00000358273.9(NF1):​c.7410T>C​(p.Asn2470=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000855 in 1,613,608 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.00052 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000040 (0 hom.)
• Consequence: NF1 ENST00000358273.9 synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:8
• Conservation: PhyloP100: 0.435

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 Benign. Variant got -17 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.5).
• BP6: Variant 17-31350271-T-C is Benign according to our data. Variant chr17-31350271-T-C is described in ClinVar as [Likely_benign]. Clinvar id is 184229.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=0.435 with no splicing effect.
• BS2: High AC in GnomAd4 at 79 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NF1	NM_001042492.3	c.7410T>C	p.Asn2470=	synonymous_variant	50/58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.3	c.7347T>C	p.Asn2449=	synonymous_variant	49/57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.7410T>C	p.Asn2470=	synonymous_variant	50/58	1	NM_001042492.3	ENSP00000351015	P1

Frequencies

GnomAD3 genomes AF: 0.000519 AC: 79 AN: 152214 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00186

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

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: 0.00

Gnomad OTH AF: 0.000479

GnomAD3 exomes AF: 0.000147 AC: 37 AN: 251318 Hom.: 0 AF XY: 0.0000736 AC XY: 10 AN XY: 135822

Gnomad AFR exome AF: 0.00228

Gnomad AMR exome AF: 0.00

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: 0.0000404 AC: 59 AN: 1461276 Hom.: 0 Cov.: 30 AF XY: 0.0000358 AC XY: 26 AN XY: 726980

Gnomad4 AFR exome AF: 0.00161

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: 0.00

Gnomad4 OTH exome AF: 0.0000497

GnomAD4 genome AF: 0.000519 AC: 79 AN: 152332 Hom.: 0 Cov.: 32 AF XY: 0.000456 AC XY: 34 AN XY: 74506

Gnomad4 AFR AF: 0.00185

Gnomad4 AMR AF: 0.0000654

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.000474

Alfa AF: 0.000848 Hom.: 0

Bravo AF: 0.000589

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:8

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:2

Likely benign, criteria provided, single submitter	clinical testing	Genetic Services Laboratory, University of Chicago	Aug 24, 2016	- -
Benign, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jan 29, 2018	Variant summary: NF1 c.7347T>C (p.Asn2449=) alters a non-conserved nucleotide resulting in a synonymous change. 5/5 computational tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The observed variant frequency within African control individuals in the gnomAD (58/24034 chrs) database is approximately 11.52 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 African origin. To our knowledge, no occurrence of c.7347T>C in individuals affected with Neurofibromatosis Type 1 and no experimental evidence demonstrating its impact on protein function have been reported. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as benign/likely benign. Based on the evidence outlined above, the variant was classified as benign. -

Neurofibromatosis, type 1 Benign:2

Likely benign, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Mar 15, 2022	- -
Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 29, 2024	- -

not provided Benign:2

Benign, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Mar 13, 2021	- -
Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Aug 02, 2021	- -

Hereditary cancer-predisposing syndrome Benign:2

Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Sep 12, 2014	This alteration is classified as likely benign based on a combination of the following: 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. -
Benign, criteria provided, single submitter	curation	Sema4, Sema4	May 30, 2021	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.50
CADD	Benign	7.9
DANN	Benign	0.69

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: rs17881903; hg19: chr17-29677289;