9-127690788-C-G

Position:

• chr9-127690788-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 5P and 3B. PM1 PM2 PP2 BP4 BP6_Moderate

The ENST00000373299.5(STXBP1):​c.1716C>G​(p.Ile572Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 8/13 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: STXBP1 ENST00000373299.5 missense
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 1.54

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:):

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in ENST00000373299.5
• 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=0.3333615).
• BP6: Variant 9-127690788-C-G is Benign according to our data. Variant chr9-127690788-C-G is described in ClinVar as [Likely_benign]. Clinvar id is 1806156.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
STXBP1	NM_001032221.6	c.1716C>G	p.Ile572Met	missense_variant	19/19	ENST00000373299.5	NP_001027392.1
STXBP1	NM_003165.6	c.*30C>G		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.1716C>G	p.Ile572Met	missense_variant	19/19	1	NM_001032221.6	ENSP00000362396.2
STXBP1	ENST00000373302.8	c.*30C>G		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: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Developmental and epileptic encephalopathy, 4 Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

May 06, 2021

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Likely benign. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with developmental and epileptic encephalopathy 4 (MIM#612164). (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from isoleucine to methionine. (I) 0219 - This variant is non-coding in an alternative transcript. This variant is not protein coding in the predominantly used transcript (UCSC, ClinVar). (I) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0503 - Missense variant consistently predicted to be tolerated by multiple in silico tools or not conserved in placental mammals with a minor amino acid change. (SB) 0600 - Variant is located in the annotated Sec1 domain (NCBI, PDB). (I) 0705 - No comparable missense variants have previous evidence for pathogenicity. (I) 0807 - This variant has no previous evidence of pathogenicity. (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1206 - This variant has been shown to be paternally inherited (LABID). (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.23
BayesDel_addAF	Pathogenic	0.16	D
BayesDel_noAF	Uncertain	0.0
CADD	Benign	20
DANN	Benign	0.95
Eigen	Benign	-0.33
Eigen_PC	Benign	-0.27
FATHMM_MKL	Uncertain	0.92	D
M_CAP	Uncertain	0.18	D
MetaRNN	Benign	0.33	T
MutationTaster	Benign	1.0	D;D
ClinPred		0.23	T
GERP RS		0.33

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: chr9-130453067;