rs375724532

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM1BP4_Moderate

The NM_199242.3(UNC13D):​c.2243C>T​(p.Ala748Val) variant causes a missense change. The variant allele was found at a frequency of 0.0000879 in 1,591,872 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A748T) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000085 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000088 ( 1 hom. )

Consequence

UNC13D
NM_199242.3 missense

Scores

2
17

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 4.63

Publications

2 publications found
Variant links:
Genes affected
UNC13D (HGNC:23147): (unc-13 homolog D) This gene encodes a protein that is a member of the UNC13 family, containing similar domain structure as other family members but lacking an N-terminal phorbol ester-binding C1 domain present in other Munc13 proteins. The protein appears to play a role in vesicle maturation during exocytosis and is involved in regulation of cytolytic granules secretion. Mutations in this gene are associated with familial hemophagocytic lymphohistiocytosis type 3, a genetically heterogeneous, rare autosomal recessive disorder. [provided by RefSeq, Jul 2008]
UNC13D Gene-Disease associations (from GenCC):
  • familial hemophagocytic lymphohistiocytosis 3
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Laboratory for Molecular Medicine, Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen
  • hereditary hemophagocytic lymphohistiocytosis
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_199242.3
BP4
Computational evidence support a benign effect (MetaRNN=0.0684858).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
UNC13DNM_199242.3 linkc.2243C>T p.Ala748Val missense_variant Exon 23 of 32 ENST00000207549.9 NP_954712.1 Q70J99-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
UNC13DENST00000207549.9 linkc.2243C>T p.Ala748Val missense_variant Exon 23 of 32 1 NM_199242.3 ENSP00000207549.3 Q70J99-1

Frequencies

GnomAD3 genomes
AF:
0.0000854
AC:
13
AN:
152222
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000482
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000963
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000913
AC:
20
AN:
218964
AF XY:
0.0000748
show subpopulations
Gnomad AFR exome
AF:
0.0000714
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000524
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000993
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000882
AC:
127
AN:
1439532
Hom.:
1
Cov.:
33
AF XY:
0.0000922
AC XY:
66
AN XY:
716080
show subpopulations
African (AFR)
AF:
0.0000600
AC:
2
AN:
33306
American (AMR)
AF:
0.00
AC:
0
AN:
43840
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25924
East Asian (EAS)
AF:
0.000254
AC:
10
AN:
39344
South Asian (SAS)
AF:
0.0000235
AC:
2
AN:
85008
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
38356
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4732
European-Non Finnish (NFE)
AF:
0.0000947
AC:
105
AN:
1109158
Other (OTH)
AF:
0.000134
AC:
8
AN:
59864
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.495
Heterozygous variant carriers
0
10
20
31
41
51
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.0000853
AC:
13
AN:
152340
Hom.:
0
Cov.:
33
AF XY:
0.0000537
AC XY:
4
AN XY:
74488
show subpopulations
African (AFR)
AF:
0.0000481
AC:
2
AN:
41584
American (AMR)
AF:
0.00
AC:
0
AN:
15310
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000965
AC:
5
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.498
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.000130
Hom.:
0
Bravo
AF:
0.0000869
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000519
AC:
2
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.0000833
AC:
10

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:2
Apr 23, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: UNC13D c.2243C>T (p.Ala748Val) results in a non-conservative amino acid change located in the MUN domain (IPR010439) of the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 8.8e-05 in 1585934 control chromosomes in the gnomAD database (v4.1 dataset), including 1 homozygote. This frequency is not higher than the estimated maximum expected for a pathogenic variant in UNC13D causing Familial Hemophagocytic Lymphohistiocytosis (0.0027), allowing no conclusion about variant significance. The variant, c.2243C>T, has been reported in the literature in heterozygous state individuals affected with (suspected) Familial Hemophagocytic Lymphohistiocytosis (e.g. Zhang_2014, McCreary_2019, Xinh_2021), however in at least one of these cases variants found in a different gene could possibly explain the phenotype (McCreary_2019). These reports do not provide unequivocal conclusions about association of the variant with Familial Hemophagocytic Lymphohistiocytosis. At least one publication reported experimental evidence evaluating an impact on protein function, and demonstrated normal activity for the variant protein (Noori_2023). The following publications have been ascertained in the context of this evaluation (PMID: 31664448, 24916509, 31664448, 34339548). ClinVar contains an entry for this variant (Variation ID: 533089). Based on the evidence outlined above, the variant was classified as VUS-possibly benign. -

Mar 24, 2021
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

DNA sequence analysis of the UNC13D gene demonstrated a sequence change, c.2243C>T, in exon 23 that results in an amino acid change, p.Ala748Val. This sequence change has been described in gnomAD with a low frequency of 0.053% (dbSNP rs375724532) in the East Asian sub-population. The p.Ala748Val change affects a moderately conserved amino acid residue located in a domain of the UNC13D protein that is not known to be functional. The p.Gln377Arg substitution appears to be benign using several in-silico pathogenicity prediction tools (SIFT, PolyPhen2, Align GVGD,REVEL). This sequence change has been reported in the heterozygous state in an individual with a clinical suspicion of hemophagocytic lymphohistiocytosis. This individual was also reported to have a heterozygous change in the PRF1 gene, suggesting a digenic mode of inheritance (PMID:24916509). Due to the lack of sufficient evidences, the clinical significance of the p.Gln377Arg change remains unknown at this time. -

Familial hemophagocytic lymphohistiocytosis 3 Uncertain:2
Jul 07, 2021
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 21, 2022
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 valine, which is neutral and non-polar, at codon 748 of the UNC13D protein (p.Ala748Val). This variant is present in population databases (rs375724532, gnomAD 0.06%). This missense change has been observed in individual(s) with hemophagocytic lymphohistiocytosis (PMID: 24916509). ClinVar contains an entry for this variant (Variation ID: 533089). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt UNC13D 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. -

not provided Uncertain:1
Aug 07, 2019
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Identified as heterozygous without a second variant in an individual in the literature (Zhang et al., 2014) with familial hemophagocytic lymphohistiocytosis who also had a single heterozygous variant in the PRF1 gene suggesting possible digenic inheritance; In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 24916509) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Benign
-0.23
T
BayesDel_noAF
Benign
-0.22
CADD
Benign
19
DANN
Benign
0.93
DEOGEN2
Benign
0.14
T;.
Eigen
Benign
0.014
Eigen_PC
Benign
0.047
FATHMM_MKL
Uncertain
0.83
D
LIST_S2
Benign
0.73
T;T
M_CAP
Benign
0.053
D
MetaRNN
Benign
0.068
T;T
MetaSVM
Benign
-0.74
T
MutationAssessor
Benign
0.90
L;L
PhyloP100
4.6
PrimateAI
Uncertain
0.67
T
PROVEAN
Benign
-0.44
N;N
REVEL
Benign
0.26
Sift
Benign
1.0
T;T
Sift4G
Benign
0.18
T;T
Polyphen
0.95
P;P
Vest4
0.24
MVP
0.73
MPC
0.10
ClinPred
0.065
T
GERP RS
4.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.11
gMVP
0.44
Mutation Taster
=88/12
polymorphism

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: rs375724532; hg19: chr17-73830461; COSMIC: COSV99256021; COSMIC: COSV99256021; API