NM_003165.6:c.733C>G

Variant names:

• chr9-127666235-C-G
• rs1554777480
• NM_003165.6:c.733C>G

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PM1 PM2 PM5 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. 13/22 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
• Publications: 1 publications found

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]

STXBP1 Gene-Disease associations (from GenCC):

• developmental and epileptic encephalopathy, 4

  Inheritance: AD, AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Ambry Genetics, PanelApp Australia, Labcorp Genetics (formerly Invitae)
• genetic developmental and epileptic encephalopathy

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• atypical Rett syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• autosomal dominant non-syndromic intellectual disability

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Dravet syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• infantile spasms

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• undetermined early-onset epileptic encephalopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• autism spectrum disorder

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
• intellectual disability

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PM1: In a hotspot region, there are 9 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 chr9-127666235-C-A is described in ClinVar as Pathogenic. ClinVar VariationId is 1298373.Status of the report is no_assertion_criteria_provided, 0 stars.
• 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 VariationId is 523457.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003165.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	STXBP1	NM_003165.6	MANE Plus Clinical	c.733C>G	p.His245Asp	missense	Exon 9 of 20	NP_003156.1	P61764-2
	STXBP1	NM_001032221.6	MANE Select	c.733C>G	p.His245Asp	missense	Exon 9 of 19	NP_001027392.1	P61764-1
	STXBP1	NM_001374306.2		c.724C>G	p.His242Asp	missense	Exon 9 of 19	NP_001361235.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	STXBP1	ENST00000373302.8	TSL:1 MANE Plus Clinical	c.733C>G	p.His245Asp	missense	Exon 9 of 20	ENSP00000362399.3	P61764-2
	STXBP1	ENST00000373299.5	TSL:1 MANE Select	c.733C>G	p.His245Asp	missense	Exon 9 of 19	ENSP00000362396.2	P61764-1
	STXBP1	ENST00000494254.4	TSL:5	c.733C>G	p.His245Asp	missense	Exon 9 of 19	ENSP00000485397.2	A0A096LP52

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	-	-	Severe global developmental delay;C4551563:Microcephaly (1)

Computational scores

Source: dbNSFP v4.9

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
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.62	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.85	D
MutationAssessor	Pathogenic	3.2	M
PhyloP100		7.9
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-8.5	D
REVEL	Pathogenic	0.91
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.85
MutPred		0.92		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
Mutation Taster		=2/98	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs1554777480; hg19: chr9-130428514;