NM_001032221.6:c.1780delA

Variant names:

• chr9-127690851-CA-C
• NM_001032221.6:c.1780delA

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.Ser594ValfsTer52) 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]

MIR3911 (HGNC:38962): (microRNA 3911) microRNAs (miRNAs) are short (20-24 nt) non-coding RNAs that are involved in post-transcriptional regulation of gene expression in multicellular organisms by affecting both the stability and translation of mRNAs. miRNAs are transcribed by RNA polymerase II as part of capped and polyadenylated primary transcripts (pri-miRNAs) that can be either protein-coding or non-coding. The primary transcript is cleaved by the Drosha ribonuclease III enzyme to produce an approximately 70-nt stem-loop precursor miRNA (pre-miRNA), which is further cleaved by the cytoplasmic Dicer ribonuclease to generate the mature miRNA and antisense miRNA star (miRNA*) products. The mature miRNA is incorporated into a RNA-induced silencing complex (RISC), which recognizes target mRNAs through imperfect base pairing with the miRNA and most commonly results in translational inhibition or destabilization of the target mRNA. The RefSeq represents the predicted microRNA stem-loop. [provided by RefSeq, Sep 2009]

ENSG00000279571 (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 rank	MANE	Protein	UniProt
STXBP1	NM_001032221.6	c.1780delA	p.Ser594ValfsTer52	frameshift_variant	Exon 19 of 19	ENST00000373299.5	NP_001027392.1
STXBP1	NM_003165.6	c.*94delA		3_prime_UTR_variant	Exon 20 of 20	ENST00000373302.8	NP_003156.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
STXBP1	ENST00000373299.5	c.1780delA	p.Ser594ValfsTer52	frameshift_variant	Exon 19 of 19	1	NM_001032221.6	ENSP00000362396.2
STXBP1	ENST00000373302.8	c.*94delA		3_prime_UTR_variant	Exon 20 of 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

May 09, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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;