chr15-38351124-CAT-C

Position:

• chr15-38351124-CAT-C

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_Strong PM2 PP5_Very_Strong

The NM_152594.3(SPRED1):​c.796_797del​(p.Met266ValfsTer4) variant causes a frameshift change. The variant allele was found at a frequency of 0.00000205 in 1,461,792 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: SPRED1 NM_152594.3 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6
• Conservation: PhyloP100: 6.21

Genes affected

SPRED1 (HGNC:20249): (sprouty related EVH1 domain containing 1) The protein encoded by this gene is a member of the Sprouty family of proteins and is phosphorylated by tyrosine kinase in response to several growth factors. The encoded protein can act as a homodimer or as a heterodimer with SPRED2 to regulate activation of the MAP kinase cascade. Defects in this gene are a cause of neurofibromatosis type 1-like syndrome (NFLS). [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 14 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 5 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 15-38351124-CAT-C is Pathogenic according to our data. Variant chr15-38351124-CAT-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 220172.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr15-38351124-CAT-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SPRED1	NM_152594.3	c.796_797del	p.Met266ValfsTer4	frameshift_variant	7/7	ENST00000299084.9	NP_689807.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SPRED1	ENST00000299084.9	c.796_797del	p.Met266ValfsTer4	frameshift_variant	7/7	1	NM_152594.3	ENSP00000299084	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461792 Hom.: 0 AF XY: 0.00000275 AC XY: 2 AN XY: 727192

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.0000187

Gnomad4 NFE exome AF: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Legius syndrome Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Feb 09, 2023	This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Met266Valfs*4) in the SPRED1 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 179 amino acid(s) of the SPRED1 protein. This premature translational stop signal has been observed in individuals with cafe au lait macules (PMID: 17704776; Invitae). ClinVar contains an entry for this variant (Variation ID: 220172). Algorithms developed to predict the effect of variants on protein structure and function are not available or were not evaluated for this variant. Experimental studies have shown that this premature translational stop signal affects SPRED1 function (PMID: 17704776, 22751498). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Center for Human Genetics, Inc, Center for Human Genetics, Inc	Nov 01, 2016	- -
Pathogenic, criteria provided, single submitter	clinical testing	Victorian Clinical Genetics Services, Murdoch Childrens Research Institute	Dec 21, 2023	Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with Legius syndrome (MIM#611431). (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0204 - Variant is predicted to result in a truncated protein (premature termination codon is NOT located at least 54 nucleotides upstream of the final exon-exon junction) with at least 1/3 of the protein sequence affected. (SP) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0701 - Other downstream protein-truncating variants comparable to the one identified in this case have very strong previous evidence for pathogenicity (DECIPHER). (SP) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. It has been identified in at least two affected individuals with cafe-au-lait spots with or without learning disabilities (PMIDs: 17704776, 25074460) and classified as likely pathogenic/pathogenic by diagnostic laboratories in ClinVar. (SP) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -
Likely pathogenic, criteria provided, single submitter	clinical testing	MGZ Medical Genetics Center	Jul 27, 2022	- -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Dec 18, 2023

Frameshift variant predicted to result in protein truncation, as the last 179 amino acids are replaced with 3 different amino acids, and other loss-of-function variants have been reported downstream in the Human Gene Mutation Database (HGMD); Observed in individuals tested at GeneDx and in published literature with clinical features of Legius syndrome (PMID: 17704776); Published functional studies demonstrate a damaging effect: inability to inhibit the RAS/MAPK pathway (PMID: 22751498, 17704776); Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 22751498, 17704776) -

Noonan syndrome and Noonan-related syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Genome Diagnostics Laboratory, The Hospital for Sick Children

Feb 01, 2020

- -

Computational scores

Source: dbNSFP v4.3

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: rs864622410; hg19: chr15-38643325;