chr17-31261768-C-A

Variant names:

• chr17-31261768-C-A
• rs754023358
• NM_001042492.3:c.4635C>A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_001042492.3(NF1):​c.4635C>A​(p.Tyr1545*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: NF1 NM_001042492.3 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 0.768

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 Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-31261768-C-A is Pathogenic according to our data. Variant chr17-31261768-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 428949.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF1	NM_001042492.3	c.4635C>A	p.Tyr1545*	stop_gained	Exon 35 of 58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.3	c.4572C>A	p.Tyr1524*	stop_gained	Exon 34 of 57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.4635C>A	p.Tyr1545*	stop_gained	Exon 35 of 58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Neurofibromatosis, type 1 Pathogenic:1

Dec 19, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Tyr1524*) in the NF1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in NF1 are known to be pathogenic (PMID: 10712197, 23913538). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with clinical features of neurofibromatosis, type 1 (PMID: 23913538, 25541118). ClinVar contains an entry for this variant (Variation ID: 428949). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Jul 11, 2014

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Y1545* pathogenic mutation (also known as c.4635C>A) located in coding exon 35 of the NF1 gene, results from a C to A substitution at nucleotide position 4635. This changes the amino acid from a tyrosine to a stop codon within coding exon 35.<span style="background-color: initial;">This pathogenic alteration was described in two individuals with neurofibromatosis type 1 out of a cohort of 565 affected individuals. (<span style="background-color: initial;">Sabbagh A, et al.Hum. Mutat. 2013 Nov; 34(11):1510-8).<span style="background-color: initial;">Additionally, this pathogenic alteration was described in one individual with neurofibromatosis type 1 out of a cohort of 113 affected individuals. (<span style="background-color: initial;">Garcia-Linares C, et al.Hum. Mutat. 2011 Jan; 32(1):78-90). In addition to the clinical data presented in the literature, s<span style="background-color: initial;">ince premature stop codons are typically deleterious in nature, this alteration is interpreted as a disease-causing mutation (ACMG Recommendations for Standards for Interpretation and Reporting of Sequence Variations. Revision 2007. Genet Med. 2008;10:294). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	35
DANN	Uncertain	1.0
Eigen	Uncertain	0.33
Eigen_PC	Benign	0.16
FATHMM_MKL	Uncertain	0.90	D
Vest4		0.99
GERP RS		0.72
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.8

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: rs754023358; hg19: chr17-29588786;