9-127690849-A-C

Position:

• chr9-127690849-A-C

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_001032221.6(STXBP1):​c.1777A>C​(p.Ser593Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,716 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/18 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: STXBP1 NM_001032221.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.23

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 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), STXBP1. . Gene score misZ 4.263 (greater than the threshold 3.09). Trascript score misZ 5.8379 (greater than threshold 3.09). GenCC has associacion of gene with intellectual disability, autosomal dominant non-syndromic intellectual disability, Dravet syndrome, undetermined early-onset epileptic encephalopathy, autism spectrum disorder, developmental and epileptic encephalopathy, West syndrome, atypical Rett syndrome, developmental and epileptic encephalopathy, 4.
• BP4: Computational evidence support a benign effect (MetaRNN=0.19297332).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
STXBP1	NM_001032221.6	c.1777A>C	p.Ser593Arg	missense_variant	19/19	ENST00000373299.5	NP_001027392.1
STXBP1	NM_003165.6	c.*91A>C		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.1777A>C	p.Ser593Arg	missense_variant	19/19	1	NM_001032221.6	ENSP00000362396.2
STXBP1	ENST00000373302.8	c.*91A>C		3_prime_UTR_variant	20/20	1	NM_003165.6	ENSP00000362399.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461716 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 727142

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

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

Oct 07, 2019

Has not been previously published as pathogenic or benign to our knowledge; Not observed in large population cohorts (Lek et al., 2016); The majority of missense variants in this gene are considered pathogenic (Stenson et al., 2014); In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.30
BayesDel_addAF	Uncertain	0.012	T
BayesDel_noAF	Benign	-0.22
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Benign	0.015	T;T;T
Eigen	Benign	-0.019
Eigen_PC	Benign	0.14
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Benign	0.70	.;T;T
M_CAP	Benign	0.069	D
MetaRNN	Benign	0.19	T;T;T
MetaSVM	Benign	-0.86	T
MutationAssessor	Benign	0.34	.;.;N
PROVEAN	Benign	-0.63	.;.;N
REVEL	Benign	0.23
Sift	Uncertain	0.0040	.;.;D
Sift4G	Uncertain	0.015	.;.;D
Polyphen		0.40	.;.;B
Vest4		0.24
MutPred		0.19		.;.;Loss of phosphorylation at S593 (P = 0.0123);
MVP		0.54
ClinPred		0.71	D
GERP RS		4.0
Varity_R		0.13

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: chr9-130453128;