X-119560346-CG-C

Position:

• chrX-119560346-CG-C

Variant summary

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

The NM_022101.4(STEEP1):​c.163delC​(p.Arg55fs) variant causes a frameshift 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 Likely pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 23)
• Consequence: STEEP1 NM_022101.4 frameshift
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 0.788

Genes affected

STEEP1 (HGNC:26239): (STING1 ER exit protein 1) While this gene is well-supported by transcript data, no functional information on its protein products is currently available. Three transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2009]

UBE2A (HGNC:12472): (ubiquitin conjugating enzyme E2 A) The modification of proteins with ubiquitin is an important cellular mechanism for targeting abnormal or short-lived proteins for degradation. Ubiquitination involves at least three classes of enzymes: ubiquitin-activating enzymes, ubiquitin-conjugating enzymes, and ubiquitin-protein ligases. This gene encodes a member of the E2 ubiquitin-conjugating enzyme family. This enzyme is required for post-replicative DNA damage repair, and may play a role in transcriptional regulation. Mutations in this gene are associated with cognitive disability. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2013]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-119560346-CG-C is Pathogenic according to our data. Variant chrX-119560346-CG-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1698675.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
STEEP1	NM_022101.4	c.163delC	p.Arg55fs	frameshift_variant	2/7	ENST00000644802.2	NP_071384.1
STEEP1	NM_001170570.2	c.163delC	p.Arg55fs	frameshift_variant	2/6		NP_001164041.1
STEEP1	NM_001170569.1	c.16delC	p.Arg6fs	frameshift_variant	2/7		NP_001164040.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
STEEP1	ENST00000644802.2	c.163delC	p.Arg55fs	frameshift_variant	2/7		NM_022101.4	ENSP00000494123.2

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 23

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Intellectual disability, X-linked 107 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

May 23, 2022

Variant summary: CXorf56 c.163delC (p.Arg55GlyfsX4) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant was absent in 183271 control chromosomes (gnomAD). To our knowledge, no occurrence of c.163delC in individuals affected with Intellectual Disability, X-Linked 107 and no experimental evidence demonstrating its impact on protein function have been reported. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

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: chrX-118694309;