chr17-75834443-C-T
Variant summary
Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP6BS1
The NM_199242.3(UNC13D):c.2180G>A(p.Arg727Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000259 in 1,565,778 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/24 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R727W) has been classified as Uncertain significance.
Frequency
Consequence
NM_199242.3 missense
Scores
Clinical Significance
Conservation
Publications
- familial hemophagocytic lymphohistiocytosis 3Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Laboratory for Molecular Medicine, Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen
- hereditary hemophagocytic lymphohistiocytosisInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
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ACMG classification
Our verdict: Likely_benign. The variant received -5 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes  0.000171  AC: 26AN: 152252Hom.:  0  Cov.: 33 show subpopulations 
GnomAD2 exomes  AF:  0.000439  AC: 76AN: 173178 AF XY:  0.000424   show subpopulations 
GnomAD4 exome  AF:  0.000269  AC: 380AN: 1413408Hom.:  0  Cov.: 33 AF XY:  0.000293  AC XY: 205AN XY: 700226 show subpopulations 
Age Distribution
GnomAD4 genome  0.000171  AC: 26AN: 152370Hom.:  0  Cov.: 33 AF XY:  0.000121  AC XY: 9AN XY: 74508 show subpopulations 
Age Distribution
ClinVar
Submissions by phenotype
not specified    Uncertain:1 
Variant summary: UNC13D c.2180G>A (p.Arg727Gln) results in a conservative amino acid change located in the MUN domain (IPR010439) of the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.00044 in 173178 control chromosomes, predominantly at a frequency of 0.0015 within the South Asian subpopulation in the gnomAD database, including 1 homozygotes. This frequency is not significantly higher than estimated for a pathogenic variant in UNC13D causing Familial Hemophagocytic Lymphohistiocytosis (0.00044 vs 0.0027), allowing no conclusion about variant significance. c.2180G>A has been reported in the literature in either the compound heterozygous or heterozygous state in individuals affected with Familial Hemophagocytic Lymphohistiocytosis or other immune dysregulation disorders, without strong evidence for causality (e.g. Sieni_2011, Batlle-Maso_2020, Xinh_2021, Allain_2023) . These reports do not provide unequivocal conclusions about association of the variant with Familial Hemophagocytic Lymphohistiocytosis. At least one publication reports experimental evidence evaluating an impact on protein function (Shibata_2018). These results suggested the variant may have mild to moderately reduced stability, but showed no damaging effect on degranulation and cytolytic activity in vitro and was capable of restoring the degranulation and cytolytic activity of a familial hemophagocytic lymphohistiocytosis cell line to levels comparable with cells transfected with the WT protein. The following publications have been ascertained in the context of this evaluation (PMID: 36155879, 32222431, 29549174, 21248318, 34339548). Three submitters have cited clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as either uncertain significance or likely benign. Based on the evidence outlined above, the variant was classified as VUS-possibly benign. -
Autoinflammatory syndrome    Uncertain:1 
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Familial hemophagocytic lymphohistiocytosis 3    Benign:1 
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Computational scores
Source: 
Splicing
 Find out detailed SpliceAI scores and Pangolin per-transcript scores at