12-109097779-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_080911.3(UNG):c.100G>A(p.Ala34Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: UNG NM_080911.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.56

Genes affected

UNG (HGNC:12572): (uracil DNA glycosylase) This gene encodes one of several uracil-DNA glycosylases. One important function of uracil-DNA glycosylases is to prevent mutagenesis by eliminating uracil from DNA molecules by cleaving the N-glycosylic bond and initiating the base-excision repair (BER) pathway. Uracil bases occur from cytosine deamination or misincorporation of dUMP residues. Alternative promoter usage and splicing of this gene leads to two different isoforms: the mitochondrial UNG1 and the nuclear UNG2. The UNG2 term was used as a previous symbol for the CCNO gene (GeneID 10309), which has been confused with this gene, in the literature and some databases. [provided by RefSeq, Nov 2010]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.14653546).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
UNG	NM_080911.3	c.100G>A	p.Ala34Thr	missense_variant	1/7	ENST00000242576.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
UNG	ENST00000242576.7	c.100G>A	p.Ala34Thr	missense_variant	1/7	1	NM_080911.3	P1
UNG	ENST00000540158.1	n.101G>A		non_coding_transcript_exon_variant	1/3	2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hyper-IgM syndrome type 5 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

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
AlphaMissense	Benign	0.074
BayesDel_addAF	Benign	-0.17	T
BayesDel_noAF	Benign	-0.48
Cadd	Benign	19
Dann	Uncertain	0.98
DEOGEN2	Benign	0.088	T
Eigen	Benign	-0.60
Eigen_PC	Benign	-0.52
FATHMM_MKL	Benign	0.60	D
LIST_S2	Benign	0.50	T
M_CAP	Uncertain	0.29	D
MetaRNN	Benign	0.15	T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	0.34	N
MutationTaster	Benign	1.0	N
PrimateAI	Uncertain	0.59	T
PROVEAN	Benign	-0.18	N
REVEL	Benign	0.072
Sift	Benign	0.25	T
Sift4G	Benign	0.12	T
Polyphen		0.0	B
Vest4		0.039
MutPred		0.24		Gain of catalytic residue at V36 (P = 0);
MVP		0.63
MPC		0.13
ClinPred		0.13	T
GERP RS		4.0
Varity_R		0.077
gMVP		0.33

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

LitVar

Other links and lift over

dbSNP: rs886048906; hg19: chr12-109535584;