NM_052874.5:c.852dupG

Variant names:

• chr16-30992835-T-TC
• rs762705451
• NM_052874.5:c.852dupG

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_052874.5(STX1B):​c.852dupG​(p.Thr285AspfsTer75) 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 (★). Synonymous variant affecting the same amino acid position (i.e. G284G) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: STX1B NM_052874.5 frameshift
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 0.263
• Publications: 2 publications found

Genes affected

STX1B (HGNC:18539): (syntaxin 1B) The protein encoded by this gene belongs to a family of proteins thought to play a role in the exocytosis of synaptic vesicles. Vesicle exocytosis releases vesicular contents and is important to various cellular functions. For instance, the secretion of transmitters from neurons plays an important role in synaptic transmission. After exocytosis, the membrane and proteins from the vesicle are retrieved from the plasma membrane through the process of endocytosis. Mutations in this gene have been identified as one cause of fever-associated epilepsy syndromes. A possible link between this gene and Parkinson's disease has also been suggested. [provided by RefSeq, Jan 2015]

STX1B Gene-Disease associations (from GenCC):

• generalized epilepsy with febrile seizures plus

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• generalized epilepsy with febrile seizures plus, type 9

  Inheritance: AD Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.0173 CDS is truncated, and there are 1 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 16-30992835-T-TC is Pathogenic according to our data. Variant chr16-30992835-T-TC is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 961584.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_052874.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	STX1B	NM_052874.5	MANE Select	c.852dupG	p.Thr285AspfsTer75	frameshift	Exon 10 of 10	NP_443106.1	P61266-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	STX1B	ENST00000215095.11	TSL:1 MANE Select	c.852dupG	p.Thr285AspfsTer75	frameshift	Exon 10 of 10	ENSP00000215095.5	P61266-1
	STX1B	ENST00000916717.1		c.849dupG	p.Thr284AspfsTer75	frameshift	Exon 10 of 10	ENSP00000586776.1
	STX1B	ENST00000565419.2	TSL:2	c.*246dupG		downstream_gene	N/A	ENSP00000455899.1	P61266-2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1460028 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 726486

African (AFR) AF: 0.00 AC: 0 AN: 33464

American (AMR) AF: 0.00 AC: 0 AN: 44686

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26100

East Asian (EAS) AF: 0.00 AC: 0 AN: 39688

South Asian (SAS) AF: 0.00 AC: 0 AN: 86212

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53214

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1110558

Other (OTH) AF: 0.00 AC: 0 AN: 60342

GnomAD4 genome Cov.: 31

ClinVar

ClinVar submissions as Germline

Significance: Likely pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	-	-	Generalized epilepsy with febrile seizures plus, type 9 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		0.26
Mutation Taster		=2/198	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs762705451; hg19: chr16-31004156; COSMIC: COSV52680622; COSMIC: COSV52680622;