rs146539065

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP5

The NM_016955.4(SEPSECS):​c.846G>A​(p.Leu282=) variant causes a synonymous change. The variant allele was found at a frequency of 0.0000651 in 1,613,808 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000066 ( 0 hom. )

Consequence

SEPSECS
NM_016955.4 synonymous

Scores

2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3U:2

Conservation

PhyloP100: 7.17
Variant links:
Genes affected
SEPSECS (HGNC:30605): (Sep (O-phosphoserine) tRNA:Sec (selenocysteine) tRNA synthase) The amino acid selenocysteine is the only amino acid that does not have its own tRNA synthetase. Instead, this amino acid is synthesized on its cognate tRNA in a three step process. The protein encoded by this gene catalyzes the third step in the process, the conversion of O-phosphoseryl-tRNA(Sec) to selenocysteinyl-tRNA(Sec).[provided by RefSeq, Mar 2011]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 4-25145092-C-T is Pathogenic according to our data. Variant chr4-25145092-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 522806.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Pathogenic=1, Uncertain_significance=2}. Variant chr4-25145092-C-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
SEPSECSNM_016955.4 linkuse as main transcriptc.846G>A p.Leu282= synonymous_variant 7/11 ENST00000382103.7

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
SEPSECSENST00000382103.7 linkuse as main transcriptc.846G>A p.Leu282= synonymous_variant 7/111 NM_016955.4 P1Q9HD40-1

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152070
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000279
AC:
7
AN:
250948
Hom.:
0
AF XY:
0.0000442
AC XY:
6
AN XY:
135826
show subpopulations
Gnomad AFR exome
AF:
0.000188
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000352
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000664
AC:
97
AN:
1461620
Hom.:
0
Cov.:
32
AF XY:
0.0000688
AC XY:
50
AN XY:
727114
show subpopulations
Gnomad4 AFR exome
AF:
0.0000598
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:
0.0000836
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000526
AC:
8
AN:
152188
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74404
show subpopulations
Gnomad4 AFR
AF:
0.0000482
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:
0.0000882
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000579
Hom.:
0
Bravo
AF:
0.0000453
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:3Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Pontocerebellar hypoplasia type 2D Pathogenic:2Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingRevvity Omics, RevvityOct 12, 2021- -
Likely pathogenic, criteria provided, single submitterresearchInstitute for Genomic Medicine, Nationwide Children's HospitalOct 01, 2021This variant was identified in two siblings with PCH type 2D and was compound-heterozygous with an initiator codon variant (c.1A>T) considered to be pathogenic. Although the c.846G>A is a synonymous change, it has been shown to disrupt splicing in experimental work by the UDN (PMID: 31607746). It is extremely rare (AF~0.00004) with no homozygotes reported in public databases including gnomAD and TopMed. We interpret the variant as likely pathogenic. -
Likely pathogenic, criteria provided, single submitterclinical testingUndiagnosed Diseases Network, NIHApr 06, 2017The c.846G>A variant in SEPSECS was shown to result in exon skipping by RNAseq. The variant is present in 6 individuals in gnomAD as heterozygotes. The variant was identifed as a compound heterozygote with c.808dupG that is a frameshift variant. -
not provided Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpNov 17, 2023This sequence change affects codon 282 of the SEPSECS mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the SEPSECS protein. This variant is present in population databases (rs146539065, gnomAD 0.02%). This variant has been observed in individual(s) with pontocerebellar hypoplasia (PMID: 31607746, 35091508). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 522806). 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. -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpAug 02, 2021Variant summary: SEPSECS c.846G>A alters a conserved nucleotide resulting in a synonymous change. 4/4 computational tools predict no significant impact on normal splicing. The variant allele was found at a frequency of 2.8e-05 in 250948 control chromosomes. c.846G>A has been reported in the literature in a 2-year-old female with severe hypotonia, global developmental delay with cerebral atrophy, hypomyelination, and central volume loss of the cerebrum who underwent trio genome sequencing and trio RNAseq from blood (Lee_2020). The patient was found to carry a paternal frameshift variant in SEPSECS (c.808dup) while the variant of interest was found on the maternal allele. RNAseq analysis showed the 130-bp exon 7 containing the synonymous variant (p. Leu282=) was skipped in about half of the mRNAs. The novel splice junction that joins exon 6 and exon 8 was detected in 25/695 additional unrelated samples without this variant, but at a much lower ratio compared with our proband and mother, suggesting that exon 7 may be susceptible to low-level skipping. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. One laboratory classified the variant as likely pathogenic, and one laboratory classified the variant as likely benign. Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.40
CADD
Benign
6.1
DANN
Benign
0.88

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.42
Details are displayed if max score is > 0.2
DS_AL_spliceai
0.42
Position offset: 41

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs146539065; hg19: chr4-25146714; API