NM_006949.4:c.358C>G

Variant names:

• chr19-7640932-C-G
• rs140745219
• NM_006949.4:c.358C>G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_006949.4(STXBP2):​c.358C>G​(p.Arg120Gly) variant causes a missense change. The variant allele was found at a frequency of 0.00000274 in 1,461,872 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R120C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: STXBP2 NM_006949.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 4.43
• Publications: 0 publications found

Genes affected

STXBP2 (HGNC:11445): (syntaxin binding protein 2) This gene encodes a member of the STXBP/unc-18/SEC1 family. The encoded protein is involved in intracellular trafficking, control of SNARE (soluble NSF attachment protein receptor) complex assembly, and the release of cytotoxic granules by natural killer cells. Mutations in this gene are associated with familial hemophagocytic lymphohistiocytosis. Alternatively spliced transcript variants encoding different isoforms have been noted for this gene. [provided by RefSeq, Jan 2013]

STXBP2 Gene-Disease associations (from GenCC):

• familial hemophagocytic lymphohistiocytosis 5

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG, LIMITED Submitted by: Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae)
• hereditary hemophagocytic lymphohistiocytosis

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• microvillus inclusion disease

  Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

ENSG00000268400 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_006949.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	STXBP2	NM_006949.4	MANE Select	c.358C>G	p.Arg120Gly	missense	Exon 6 of 19	NP_008880.2
	STXBP2	NM_001272034.2		c.391C>G	p.Arg131Gly	missense	Exon 6 of 19	NP_001258963.1
	STXBP2	NM_001127396.3		c.349C>G	p.Arg117Gly	missense	Exon 6 of 19	NP_001120868.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	STXBP2	ENST00000221283.10	TSL:1 MANE Select	c.358C>G	p.Arg120Gly	missense	Exon 6 of 19	ENSP00000221283.4
	STXBP2	ENST00000414284.6	TSL:1	c.349C>G	p.Arg117Gly	missense	Exon 6 of 19	ENSP00000409471.1
	STXBP2	ENST00000597068.5	TSL:1	n.358C>G		non_coding_transcript_exon	Exon 6 of 19	ENSP00000471327.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461872 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727242

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000360 AC: 4 AN: 1112000

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00000192981), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.21
BayesDel_addAF	Uncertain	0.084	D
BayesDel_noAF	Benign	-0.12
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Benign	0.41	T
Eigen	Benign	-0.15
Eigen_PC	Benign	-0.071
FATHMM_MKL	Uncertain	0.86	D
LIST_S2	Pathogenic	0.97	D
M_CAP	Uncertain	0.15	D
MetaRNN	Uncertain	0.56	D
MetaSVM	Benign	-0.35	T
MutationAssessor	Benign	1.9	L
PhyloP100		4.4
PrimateAI	Benign	0.48	T
PROVEAN	Uncertain	-3.2	D
REVEL	Uncertain	0.41
Sift	Uncertain	0.0030	D
Sift4G	Uncertain	0.0060	D
Polyphen		0.12	B
Vest4		0.43
MutPred		0.44		Gain of relative solvent accessibility (P = 0.0522)
MVP		0.84
MPC		0.61
ClinPred		0.95	D
GERP RS		3.5
Varity_R		0.58
gMVP		0.58
Mutation Taster		=58/42	polymorphism

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

Other links and lift over

dbSNP: rs140745219; hg19: chr19-7705818;