1-25800195-TTCCCGGGCCGCCGGCAGCCGCCGCCAGCCGCAGCCATGGGCCGGGCCCGGCCGGGCCAACGCGGGCCGCCCAGCCCCGGCCCCGCCGCGCAGCC-T

Position:

• chr1-25800195-TTCCCGGGCCGCCGGCAGCCGCCGCCAGCCGCAGCCATGGGCCGGGCCCGGCCGGGCCAACGCGGGCCGCCCAGCCCCGGCCCCGCCGCGCAGCC-T

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1 PP5_Moderate

The NM_020451.3(SELENON):​c.-30_64del variant causes a start lost, 5 prime UTR change involving the alteration of a non-conserved nucleotide. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: 𝑓 0.0 (0 hom., cov: 30)
  • Exomes 𝑓: 0.000043 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: SELENON NM_020451.3 start_lost, 5_prime_UTR
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 0.881

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]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PVS1: Start lost variant, no new inframe start found.
• PP5: Variant 1-25800195-TTCCCGGGCCGCCGGCAGCCGCCGCCAGCCGCAGCCATGGGCCGGGCCCGGCCGGGCCAACGCGGGCCGCCCAGCCCCGGCCCCGCCGCGCAGCC-T is Pathogenic according to our data. Variant chr1-25800195-TTCCCGGGCCGCCGGCAGCCGCCGCCAGCCGCAGCCATGGGCCGGGCCCGGCCGGGCCAACGCGGGCCGCCCAGCCCCGGCCCCGCCGCGCAGCC-T is described in ClinVar as [Pathogenic]. Clinvar id is 2418838.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr1-25800195-TTCCCGGGCCGCCGGCAGCCGCCGCCAGCCGCAGCCATGGGCCGGGCCCGGCCGGGCCAACGCGGGCCGCCCAGCCCCGGCCCCGCCGCGCAGCC-T is described in Lovd as [Pathogenic]. Variant chr1-25800195-TTCCCGGGCCGCCGGCAGCCGCCGCCAGCCGCAGCCATGGGCCGGGCCCGGCCGGGCCAACGCGGGCCGCCCAGCCCCGGCCCCGCCGCGCAGCC-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SELENON	NM_020451.3	c.-30_64del		start_lost, 5_prime_UTR_variant	1/13	ENST00000361547.7
SELENON	NM_206926.2	c.-30_64del		start_lost, 5_prime_UTR_variant	1/12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SELENON	ENST00000361547.7	c.-30_64del		start_lost, 5_prime_UTR_variant	1/13	1	NM_020451.3
SELENON	ENST00000354177.9			coding_sequence_variant, 5_prime_UTR_variant	1/12	5
SELENON	ENST00000374315.1	c.-30_64del		start_lost, 5_prime_UTR_variant	1/12	5		P1
SELENON	ENST00000494537.2			coding_sequence_variant, 5_prime_UTR_variant, NMD_transcript_variant	1/13	3

Frequencies

GnomAD3 genomes AF: 0.00 AC: 0 AN: 142028 Hom.: 0 Cov.: 30 FAILED QC

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 0.0000434 AC: 8 AN: 184158 Hom.: 0 AF XY: 0.0000575 AC XY: 5 AN XY: 86910

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: 0.00

Gnomad4 NFE exome AF: 0.0000476

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Data not reliable, filtered out with message: AC0;AS_VQSR AF: 0.00 AC: 0 AN: 142028 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 68888

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Eichsfeld type congenital muscular dystrophy Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 11, 2022

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. For these reasons, this variant has been classified as Pathogenic. This variant is also known as c.-34_60del. Disruption of the initiator codon has been observed in individuals with SELENON-related conditions (PMID: 12192640, 21670436, 23394784, 28558865). 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

Splicing

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr1-26126686;