6-31959215-G-T

Variant names:

• chr6-31959215-G-T
• rs981582662
• NM_006929.5:c.22+1G>T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_006929.5(SKIC2):​c.22+1G>T variant causes a splice donor, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000687 in 1,456,508 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: SKIC2 NM_006929.5 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 2.94

Genes affected

SKIC2 (HGNC:10898): (SKI2 subunit of superkiller complex) DEAD box proteins, characterized by the conserved motif Asp-Glu-Ala-Asp (DEAD), are putative RNA helicases. They are implicated in a number of cellular processes involving alteration of RNA secondary structure such as translation initiation, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. Based on their distribution patterns, some members of this family are believed to be involved in embryogenesis, spermatogenesis, and cellular growth and division. This gene encodes a DEAD box protein, which is a human homologue of yeast SKI2 and may be involved in antiviral activity by blocking translation of poly(A) deficient mRNAs. This gene is located in the class III region of the major histocompatibility complex. [provided by RefSeq, Jul 2008]

NELFE (HGNC:13974): (negative elongation factor complex member E) The protein encoded by this gene is part of a complex termed negative elongation factor (NELF) which represses RNA polymerase II transcript elongation. This protein bears similarity to nuclear RNA-binding proteins; however, it has not been demonstrated that this protein binds RNA. The protein contains a tract of alternating basic and acidic residues, largely arginine (R) and aspartic acid (D). The gene localizes to the major histocompatibility complex (MHC) class III region on chromosome 6. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 6-31959215-G-T is Pathogenic according to our data. Variant chr6-31959215-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2999212.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SKIC2	NM_006929.5	c.22+1G>T		splice_donor_variant, intron_variant	Intron 1 of 27	ENST00000375394.7	NP_008860.4
NELFE	NM_002904.6	c.-332C>A		upstream_gene_variant		ENST00000375429.8	NP_002895.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SKIC2	ENST00000375394.7	c.22+1G>T		splice_donor_variant, intron_variant	Intron 1 of 27	1	NM_006929.5	ENSP00000364543.2
NELFE	ENST00000375429.8	c.-332C>A		upstream_gene_variant		1	NM_002904.6	ENSP00000364578.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000405 AC: 1 AN: 246884 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 133896

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000305

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.87e-7 AC: 1 AN: 1456508 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 724420

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000232

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Nov 24, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects a donor splice site in intron 1 of the SKIV2L gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in SKIV2L are known to be pathogenic (PMID: 22444670). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with SKIV2L-related conditions. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.32
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Uncertain	0.83	D
GERP RS		5.3

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.97		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.97		Position offset: -1

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

Publications

LitVar

Other links and lift over

dbSNP: rs981582662; hg19: chr6-31926992;