chr9-127666235-C-G

Position:

• chr9-127666235-C-G

Variant summary

Our verdict is Pathogenic. Variant got 13 ACMG points: 13P and 0B. PM1 PM2 PM5 PP2 PP3_Strong PP5_Moderate

The NM_003165.6(STXBP1):​c.733C>G​(p.His245Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. H245N) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: STXBP1 NM_003165.6 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.91

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]

ACMG classification

Verdict is Pathogenic. Variant got 13 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 4 uncertain in NM_003165.6
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr9-127666236-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 160070.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• 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 5.8329 (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.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.992
• PP5: Variant 9-127666235-C-G is Pathogenic according to our data. Variant chr9-127666235-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 523457.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
STXBP1	NM_003165.6	c.733C>G	p.His245Asp	missense_variant	9/20	ENST00000373302.8
STXBP1	NM_001032221.6	c.733C>G	p.His245Asp	missense_variant	9/19	ENST00000373299.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
STXBP1	ENST00000373302.8	c.733C>G	p.His245Asp	missense_variant	9/20	1	NM_003165.6	P3
STXBP1	ENST00000373299.5	c.733C>G	p.His245Asp	missense_variant	9/19	1	NM_001032221.6	A1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Severe global developmental delay;C4551563:Microcephaly Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Centre for Mendelian Genomics, University Medical Centre Ljubljana

Jan 01, 2017

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.43	D
BayesDel_noAF	Pathogenic	0.39
CADD	Pathogenic	28
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.50	.;D;.;D;.;D;D
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D;.;D;D;D;D;D
M_CAP	Pathogenic	0.62	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.85	D
MutationAssessor	Pathogenic	3.2	.;.;M;.;.;.;M
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-8.5	.;.;D;.;.;.;D
REVEL	Pathogenic	0.91
Sift	Pathogenic	0.0	.;.;D;.;.;.;D
Sift4G	Pathogenic	0.0	.;.;D;.;.;.;D
Polyphen		1.0	.;.;D;.;.;.;D
Vest4		0.85, 0.84
MutPred		0.92		.;.;Loss of catalytic residue at L247 (P = 0.0769);Loss of catalytic residue at L247 (P = 0.0769);Loss of catalytic residue at L247 (P = 0.0769);.;Loss of catalytic residue at L247 (P = 0.0769);
MVP		0.95
MPC		2.5
ClinPred		1.0	D
GERP RS		5.7
Varity_R		0.97
gMVP		1.0

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

LitVar

Other links and lift over

dbSNP: rs1554777480; hg19: chr9-130428514;