chr17-31226467-G-A

Position:

• chr17-31226467-G-A

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_Strong BP6_Very_Strong BP7 BA1

The NM_001042492.3(NF1):​c.2034G>A​(p.Pro678Pro) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.336 in 1,613,246 control chromosomes in the GnomAD database, including 99,275 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

• Frequency:
  • Genomes: 𝑓 0.43 (15875 hom., cov: 31)
  • Exomes 𝑓: 0.33 (83400 hom.)
• Consequence: NF1 NM_001042492.3 synonymous
• Clinical Significance: Benign criteria provided, multiple submitters, no conflicts B:19
• Conservation: PhyloP100: -1.28

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 (HGNC:):

ACMG classification

Verdict is Benign. Variant got -21 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.71).
• BP6: Variant 17-31226467-G-A is Benign according to our data. Variant chr17-31226467-G-A is described in ClinVar as [Benign]. Clinvar id is 183826.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-31226467-G-A is described in Lovd as [Benign].
• BP7: Synonymous conserved (PhyloP=-1.28 with no splicing effect.
• BA1: GnomAd4 highest subpopulation (AFR) allele frequency at 95% confidence interval = 0.667 is higher than 0.05.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NF1	NM_001042492.3	c.2034G>A	p.Pro678Pro	synonymous_variant	18/58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.3	c.2034G>A	p.Pro678Pro	synonymous_variant	18/57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.2034G>A	p.Pro678Pro	synonymous_variant	18/58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes AF: 0.425 AC: 64514 AN: 151726 Hom.: 15853 Cov.: 31

Gnomad AFR AF: 0.674

Gnomad AMI AF: 0.280

Gnomad AMR AF: 0.433

Gnomad ASJ AF: 0.234

Gnomad EAS AF: 0.524

Gnomad SAS AF: 0.382

Gnomad FIN AF: 0.343

Gnomad MID AF: 0.203

Gnomad NFE AF: 0.295

Gnomad OTH AF: 0.363

GnomAD3 exomes AF: 0.378 AC: 94603 AN: 250420 Hom.: 19736 AF XY: 0.362 AC XY: 49055 AN XY: 135352

Gnomad AFR exome AF: 0.683

Gnomad AMR exome AF: 0.494

Gnomad ASJ exome AF: 0.226

Gnomad EAS exome AF: 0.519

Gnomad SAS exome AF: 0.370

Gnomad FIN exome AF: 0.338

Gnomad NFE exome AF: 0.301

Gnomad OTH exome AF: 0.330

GnomAD4 exome AF: 0.327 AC: 477803 AN: 1461402 Hom.: 83400 Cov.: 52 AF XY: 0.326 AC XY: 236867 AN XY: 726990

Gnomad4 AFR exome AF: 0.686

Gnomad4 AMR exome AF: 0.485

Gnomad4 ASJ exome AF: 0.228

Gnomad4 EAS exome AF: 0.540

Gnomad4 SAS exome AF: 0.368

Gnomad4 FIN exome AF: 0.343

Gnomad4 NFE exome AF: 0.301

Gnomad4 OTH exome AF: 0.334

GnomAD4 genome AF: 0.425 AC: 64585 AN: 151844 Hom.: 15875 Cov.: 31 AF XY: 0.430 AC XY: 31920 AN XY: 74218

Gnomad4 AFR AF: 0.673

Gnomad4 AMR AF: 0.433

Gnomad4 ASJ AF: 0.234

Gnomad4 EAS AF: 0.524

Gnomad4 SAS AF: 0.383

Gnomad4 FIN AF: 0.343

Gnomad4 NFE AF: 0.295

Gnomad4 OTH AF: 0.363

Alfa AF: 0.315 Hom.: 5213

Bravo AF: 0.442

Asia WGS AF: 0.462 AC: 1605 AN: 3478

EpiCase AF: 0.279

EpiControl AF: 0.278

ClinVar

Significance: Benign

Submissions summary: Benign:19

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:5

Benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -
Benign, no assertion criteria provided	clinical testing	Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+	-	- -
Benign, no assertion criteria provided	clinical testing	Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen	-	- -
Benign, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Feb 28, 2017	p.Pro678Pro in exon 18 of NF1: This variant is not expected to have clinical sig nificance because it does not alter an amino acid residue and is not located wit hin the splice consensus sequence. It has been identified in 30% (20030/66512) o f European chromosomes and 68% (7103/10384) of African chromosomes by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org; dbSNP rs2285892). -
Benign, criteria provided, single submitter	clinical testing	PreventionGenetics, part of Exact Sciences	-	- -

not provided Benign:5

Benign, criteria provided, single submitter	clinical testing	GeneDx	Jan 26, 2016	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Benign, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Apr 07, 2021	- -
Benign, criteria provided, single submitter	clinical testing	Athena Diagnostics	Jul 12, 2017	- -
Benign, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	May 11, 2016	Variant summary: The NF1 c.2034G>A (p.Pro678Pro) variant involves the alteration of a non-conserved nucleotide, resulting in a synonymous change. One in silico tool predicts a polymorphism outcome for this variant. 5/5 splice prediction tools predict no significant impact on normal splicing. ESE finder predicts that this variant may affect multiple ESE sites. However, these predictions have yet to be confirmed by functional studies. This variant was found in 46285/120934 control chromosomes (9925 homozygotes) at a frequency of 0.3827294, which is approximately 1837 times the estimated maximal expected allele frequency of a pathogenic NF1 variant (0.0002084), suggesting this variant is likely a benign polymorphism. In addition, one clinical diagnostic laboratory classified this variant as benign. Taken together, this variant is classified as benign. -
Benign, criteria provided, single submitter	not provided	Breakthrough Genomics, Breakthrough Genomics	-	- -

Neurofibromatosis, type 1 Benign:3

Benign, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Sep 05, 2021	- -
Benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 12, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -
Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Feb 01, 2024	- -

Neurofibromatosis, familial spinal Benign:2

Benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 12, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -
Benign, criteria provided, single submitter	clinical testing	KCCC/NGS Laboratory, Kuwait Cancer Control Center	Jul 07, 2023	- -

Neurofibromatosis-Noonan syndrome Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Café-au-lait macules with pulmonary stenosis Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype Benign:1

Benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 11, 2014

This alteration is classified as 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

Benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 10, 2014

This alteration is classified as 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.71
CADD	Benign	3.6
DANN	Benign	0.56

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs2285892; hg19: chr17-29553485; COSMIC: COSV62191601; COSMIC: COSV62191601;