9-127690851-CA-C

Position:

• chr9-127690851-CA-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The NM_001032221.6(STXBP1):​c.1780delA​(p.Ser594fs) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: STXBP1 NM_001032221.6 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.88

Genes affected

STXBP1 (HGNC:11444): (syntaxin binding protein 1) This gene encodes a syntaxin-binding protein. The encoded protein appears to play a role in release of neurotransmitters via regulation of syntaxin, a transmembrane attachment protein receptor. Mutations in this gene have been associated with infantile epileptic encephalopathy-4. Alternatively spliced transcript variants have been described. [provided by RefSeq, Feb 2010]

PTRH1 (HGNC:27039): (peptidyl-tRNA hydrolase 1 homolog) Enables RNA binding activity. [provided by Alliance of Genome Resources, Apr 2022]

STXBP1 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 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 0.0028 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
STXBP1	NM_001032221.6	c.1780delA	p.Ser594fs	frameshift_variant	19/19	ENST00000373299.5	NP_001027392.1
STXBP1	NM_003165.6	c.*94delA		3_prime_UTR_variant	20/20	ENST00000373302.8	NP_003156.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
STXBP1	ENST00000373299.5	c.1780delA	p.Ser594fs	frameshift_variant	19/19	1	NM_001032221.6	ENSP00000362396.2
STXBP1	ENST00000373302.8	c.*94delA		3_prime_UTR_variant	20/20	1	NM_003165.6	ENSP00000362399.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

May 09, 2024

Not observed at significant frequency in large population cohorts (gnomAD); Frameshift variant predicted to result in abnormal protein length as the last 1 amino acids are replaced with 51 different amino acids; De novo variant with confirmed parentage in a patient referred for genetic testing at GeneDx; however, the reported clinical features are only partially consistent with the features typically observed in individuals with pathogenic variants in this gene; Has not been previously published as pathogenic or benign to our knowledge; Reported using an alternate transcript of the gene -

Computational scores

Source: dbNSFP v4.3

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr9-130453130;