rs759514227

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_006949.4(STXBP2):​c.1648G>A​(p.Ala550Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000205 in 1,611,564 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000022 ( 0 hom. )

Consequence

STXBP2
NM_006949.4 missense

Scores

8
10
1

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 8.04

Publications

0 publications found
Variant links:
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

PP3
MetaRNN computational evidence supports a deleterious effect, 0.846

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
STXBP2NM_006949.4 linkc.1648G>A p.Ala550Thr missense_variant Exon 18 of 19 ENST00000221283.10 NP_008880.2 Q15833-1Q53GF4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
STXBP2ENST00000221283.10 linkc.1648G>A p.Ala550Thr missense_variant Exon 18 of 19 1 NM_006949.4 ENSP00000221283.4 Q15833-1
ENSG00000268400ENST00000698368.1 linkn.*1751G>A non_coding_transcript_exon_variant Exon 20 of 20 ENSP00000513686.1 A0A8V8TM65
ENSG00000268400ENST00000698368.1 linkn.*1751G>A 3_prime_UTR_variant Exon 20 of 20 ENSP00000513686.1 A0A8V8TM65

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152164
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000329
AC:
8
AN:
243502
AF XY:
0.0000302
show subpopulations
Gnomad AFR exome
AF:
0.0000655
Gnomad AMR exome
AF:
0.0000586
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000915
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000219
AC:
32
AN:
1459400
Hom.:
0
Cov.:
76
AF XY:
0.0000262
AC XY:
19
AN XY:
725866
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33402
American (AMR)
AF:
0.0000449
AC:
2
AN:
44498
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26050
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39568
South Asian (SAS)
AF:
0.0000582
AC:
5
AN:
85904
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52984
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5752
European-Non Finnish (NFE)
AF:
0.0000198
AC:
22
AN:
1110978
Other (OTH)
AF:
0.0000332
AC:
2
AN:
60264
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.463
Heterozygous variant carriers
0
3
6
9
12
15
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152164
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74316
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41434
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000329
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.0000412
AC:
5

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Familial hemophagocytic lymphohistiocytosis 5 Uncertain:1
Oct 24, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 550 of the STXBP2 protein (p.Ala550Thr). This variant is present in population databases (rs759514227, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with STXBP2-related conditions. ClinVar contains an entry for this variant (Variation ID: 565511). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on STXBP2 protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.50
BayesDel_addAF
Uncertain
0.12
D
BayesDel_noAF
Pathogenic
0.17
CADD
Pathogenic
28
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.69
.;D;.;D
Eigen
Pathogenic
0.94
Eigen_PC
Pathogenic
0.89
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Pathogenic
0.99
D;D;D;D
M_CAP
Uncertain
0.26
D
MetaRNN
Pathogenic
0.85
D;D;D;D
MetaSVM
Uncertain
0.62
D
MutationAssessor
Pathogenic
3.3
.;M;.;.
PhyloP100
8.0
PrimateAI
Uncertain
0.64
T
PROVEAN
Uncertain
-3.7
D;D;D;.
REVEL
Pathogenic
0.83
Sift
Uncertain
0.0010
D;D;D;.
Sift4G
Uncertain
0.0020
D;D;D;D
Polyphen
1.0
.;D;D;.
Vest4
0.65
MVP
0.93
MPC
0.84
ClinPred
0.90
D
GERP RS
5.3
RBP_binding_hub_radar
0.97
RBP_regulation_power_radar
2.8
Varity_R
0.94
gMVP
0.77
Mutation Taster
=43/57
disease causing

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

Other links and lift over

dbSNP: rs759514227; hg19: chr19-7712349; API