17-75827947-C-T

Variant names:

• chr17-75827947-C-T
• rs886053421
• NM_199242.3:c.*18G>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_199242.3(UNC13D):​c.*18G>A variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000755 in 1,456,076 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000076 (0 hom.)
• Consequence: UNC13D NM_199242.3 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.874
• Publications: 0 publications found

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

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.78).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
UNC13D	NM_199242.3	c.*18G>A		3_prime_UTR_variant	Exon 32 of 32	ENST00000207549.9	NP_954712.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
UNC13D	ENST00000207549.9	c.*18G>A		3_prime_UTR_variant	Exon 32 of 32	1	NM_199242.3	ENSP00000207549.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000755 AC: 11 AN: 1456076 Hom.: 0 Cov.: 31 AF XY: 0.00000552 AC XY: 4 AN XY: 724180

African (AFR) AF: 0.00 AC: 0 AN: 33320

American (AMR) AF: 0.00 AC: 0 AN: 44538

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26076

East Asian (EAS) AF: 0.00 AC: 0 AN: 39520

South Asian (SAS) AF: 0.00 AC: 0 AN: 85680

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51794

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4372

European-Non Finnish (NFE) AF: 0.00000900 AC: 10 AN: 1110788

Other (OTH) AF: 0.0000167 AC: 1 AN: 59988

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial hemophagocytic lymphohistiocytosis 3 Uncertain:1

Jan 12, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.78
CADD	Benign	3.9
DANN	Benign	0.82
PhyloP100		-0.87
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.2

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: rs886053421; hg19: chr17-73824028;