Variant 1-25800205-GCCGGCAGCCGCCGCCAGCCGCAGCCATGGGCCGGGCCCGGCCGGGCCAACGCGGGCCGCCCAGCCCCGGCCCCGCCGCGCAGCCTCCCGCGCCACCGCGCCGCCGCGCCCGTTCCCTGGCGCTGCTCGGAGCCCTGCTGGCCGCCGCCGCTGCCGCCGCCGTCCGGGTCTGCGCCCGCCACGCCGAGGCCCAGGCGGCCGCGCGGCAGGT-G details in Genebe, Genetics Data Aggregator

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP5_Moderate

The NM_020451.3(SELENON):c.-21_183+6del(p.Met1_Gln61del) variant causes a start lost, conservative inframe deletion, splice region change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★).

Frequency

Genomes: not found (cov: 30)

Consequence

SELENON
NM_020451.3 start_lost, conservative_inframe_deletion, splice_region

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 0.989

Variant links:

Genes affected

SELENON (HGNC:15999): (selenoprotein N) This gene encodes a glycoprotein that is localized in the endoplasmic reticulum. It plays an important role in cell protection against oxidative stress, and in the regulation of redox-related calcium homeostasis. Mutations in this gene are associated with early onset muscle disorders, referred to as SEPN1-related myopathy. SEPN1-related myopathy consists of 4 autosomal recessive disorders, originally thought to be separate entities: rigid spine muscular dystrophy (RSMD1), the classical form of multiminicore disease, desmin related myopathy with Mallory-body like inclusions, and congenital fiber-type disproportion (CFTD). This protein is a selenoprotein, containing the rare amino acid selenocysteine (Sec). Sec is encoded by the UGA codon, which normally signals translation termination. The 3' UTRs of selenoprotein mRNAs contain a conserved stem-loop structure, designated the Sec insertion sequence (SECIS) element, that is necessary for the recognition of UGA as a Sec codon, rather than as a stop signal. A second stop-codon redefinition element (SRE) adjacent to the UGA codon has been identified in this gene (PMID:15791204). SRE is a phylogenetically conserved stem-loop structure that stimulates readthrough at the UGA codon, and augments the Sec insertion efficiency by SECIS. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Dec 2016]

SELENON links:

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 1-25800205-GCCGGCAGCCGCCGCCAGCCGCAGCCATGGGCCGGGCCCGGCCGGGCCAACGCGGGCCGCCCAGCCCCGGCCCCGCCGCGCAGCCTCCCGCGCCACCGCGCCGCCGCGCCCGTTCCCTGGCGCTGCTCGGAGCCCTGCTGGCCGCCGCCGCTGCCGCCGCCGTCCGGGTCTGCGCCCGCCACGCCGAGGCCCAGGCGGCCGCGCGGCAGGT-G is Pathogenic according to our data. Variant chr1-25800205-GCCGGCAGCCGCCGCCAGCCGCAGCCATGGGCCGGGCCCGGCCGGGCCAACGCGGGCCGCCCAGCCCCGGCCCCGCCGCGCAGCCTCCCGCGCCACCGCGCCGCCGCGCCCGTTCCCTGGCGCTGCTCGGAGCCCTGCTGGCCGCCGCCGCTGCCGCCGCCGTCCGGGTCTGCGCCCGCCACGCCGAGGCCCAGGCGGCCGCGCGGCAGGT-G is described in ClinVar as [Pathogenic]. Clinvar id is 2113172.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SELENON	NM_020451.3 link	c.-21_183+6del	p.Met1_Gln61del	start_lost, conservative_inframe_deletion, splice_region_variant	1/13	ENST00000361547.7	NP_065184.2	Q9NZV5-1
SELENON	NM_020451.3 link	c.-21_189del		splice_donor_variant, splice_region_variant, 5_prime_UTR_variant, intron_variant	1/13	ENST00000361547.7	NP_065184.2	Q9NZV5-1
SELENON	NM_206926.2 link	c.-21_183+6del	p.Met1_Gln61del	start_lost, conservative_inframe_deletion, splice_region_variant	1/12		NP_996809.1	Q9NZV5-2
SELENON	NM_206926.2 link	c.-21_189del		splice_donor_variant, splice_region_variant, 5_prime_UTR_variant, intron_variant	1/12		NP_996809.1	Q9NZV5-2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SELENON	ENST00000361547.7 link	c.-25_183+2del	p.Met1fs	frameshift_variant, start_lost, splice_region_variant	1/13	1	NM_020451.3	ENSP00000355141.2		Q9NZV5-1
SELENON	ENST00000361547 link	c.-25_185del		splice_donor_variant, 5_prime_UTR_variant, intron_variant	1/13	1	NM_020451.3	ENSP00000355141.2		Q9NZV5-1

Frequencies

GnomAD3 genomes

Cov.:

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome

Cov.:

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Eichsfeld type congenital muscular dystrophy

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 09, 2023

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 2113172). Disruption of the initiator codon has been observed in individuals with clinical features of SELENON-related conditions (PMID: 12192640, 16779558). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the gnomAD database. This sequence change affects the initiator methionine of the SELENON mRNA. The next in-frame methionine is located at codon 85. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

No publications associated with this variant yet.