rs17881788

chr17-31336880-C-T

Variant summary

Our verdict is Benign. Variant got -19 ACMG points: 0P and 19B. BP4_Moderate BP6_Very_Strong BP7 BS1 BS2

The NM_001042492.3(NF1):c.6393C>T(p.His2131=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00108 in 1,612,824 control chromosomes in the GnomAD database, including 20 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0059 (7 hom., cov: 32)
  • Exomes 𝑓: 0.00057 (13 hom.)
• Consequence: NF1 NM_001042492.3 synonymous
• Clinical Significance: Benign criteria provided, multiple submitters, no conflicts B:17
• Conservation: PhyloP100: 2.22

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 -19 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.45).
• BP6: Variant 17-31336880-C-T is Benign according to our data. Variant chr17-31336880-C-T is described in ClinVar as [Benign]. Clinvar id is 184228.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-31336880-C-T is described in Lovd as [Benign].
• BP7: Synonymous conserved (PhyloP=2.22 with no splicing effect.
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00594 (904/152306) while in subpopulation AFR AF= 0.021 (872/41576). AF 95% confidence interval is 0.0198. There are 7 homozygotes in gnomad4. There are 433 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.
• BS2: High AC in GnomAd at 903 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NF1	NM_001042492.3	c.6393C>T	p.His2131=	synonymous_variant	42/58	ENST00000358273.9
NF1	NM_000267.3	c.6330C>T	p.His2110=	synonymous_variant	41/57

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NF1	ENST00000358273.9	c.6393C>T	p.His2131=	synonymous_variant	42/58	1	NM_001042492.3	P1

Frequencies

GnomAD3 genomes AF: 0.00593 AC: 903 AN: 152188 Hom.: 7 Cov.: 32

Gnomad AFR AF: 0.0210

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00151

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: 0.0000294

Gnomad OTH AF: 0.00335

GnomAD3 exomes AF: 0.00151 AC: 377 AN: 250394 Hom.: 7 AF XY: 0.00111 AC XY: 150 AN XY: 135470

Gnomad AFR exome AF: 0.0215

Gnomad AMR exome AF: 0.000434

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000352

Gnomad OTH exome AF: 0.00114

GnomAD4 exome AF: 0.000573 AC: 837 AN: 1460518 Hom.: 13 Cov.: 34 AF XY: 0.000535 AC XY: 389 AN XY: 726648

Gnomad4 AFR exome AF: 0.0225

Gnomad4 AMR exome AF: 0.000492

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000540

Gnomad4 OTH exome AF: 0.000878

GnomAD4 genome AF: 0.00594 AC: 904 AN: 152306 Hom.: 7 Cov.: 32 AF XY: 0.00581 AC XY: 433 AN XY: 74476

Gnomad4 AFR AF: 0.0210

Gnomad4 AMR AF: 0.00150

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00332

Alfa AF: 0.00418 Hom.: 5

Bravo AF: 0.00662

Asia WGS AF: 0.00173 AC: 6 AN: 3478

ClinVar

Significance: Benign

Submissions summary: Benign:17

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:5

Benign, criteria provided, single submitter	clinical testing	Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine	Nov 24, 2014	His2131His in exon 42 of NF1: This variant is not expected to have clinical sign ificance because it does not alter an amino acid residue and is not located with in the splice consensus sequence. It has been identified in 2.0% (89/4406) of Af rican American chromosomes from a broad population by the NHLBI Exome Sequencing Project (http://evs.gs.washington.edu/EVS; dbSNP rs17881788). -
Benign, criteria provided, single submitter	clinical testing	Genetic Services Laboratory, University of Chicago	Nov 14, 2016	- -
Benign, criteria provided, single submitter	clinical testing	PreventionGenetics, part of Exact Sciences	-	- -
Benign, no assertion criteria provided	clinical testing	Genome Diagnostics Laboratory, Amsterdam University Medical Center	-	- -
Benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -

Neurofibromatosis, type 1 Benign:4

Benign, criteria provided, single submitter	clinical testing	Genome Diagnostics Laboratory, The Hospital for Sick Children	Oct 26, 2020	- -
Benign, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Mar 15, 2022	- -
Benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 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	Invitae	Feb 01, 2024	- -

not provided Benign:3

Benign, criteria provided, single submitter	clinical testing	GeneDx	Sep 20, 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	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jul 06, 2017	Variant summary: The NF1 c.6330C>T (p.His2110His) variant involves the alteration of a conserved nucleotide, resulting in a synonymous change. One in silico tool predicts a damaging outcome for this variant. 5/5 splice prediction tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant of interest has been found in a large, broad control population, ExAC in 228/121380 control chromosomes at a frequency of 0.0018784, which is approximately 9 times the estimated maximal expected allele frequency of a pathogenic NF1 variant (0.0002084), suggesting this variant is likely a benign polymorphism. In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as benign/likely benign. The variant of interest has not, to our knowledge, been reported in affected individuals via publications and/or reputable databases/clinical diagnostic laboratories; nor evaluated for functional impact by in vivo/vitro studies. Taken together, this variant is classified as benign. -
Benign, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Jun 07, 2017	- -

Neurofibromatosis, familial spinal Benign:2

Benign, criteria provided, single submitter	clinical testing	KCCC/NGS Laboratory, Kuwait Cancer Control Center	Jul 07, 2023	- -
Benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 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. -

Neurofibromatosis-Noonan syndrome Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 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 13, 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 Benign:1

Benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 28, 2014

General population or subpopulation frequency is too high to be a pathogenic mutation based on disease/syndrome prevalence and penetrance -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.45
Cadd	Benign	5.9
Dann	Benign	0.53

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs17881788; hg19: chr17-29663898; COSMIC: COSV62201959; COSMIC: COSV62201959;