15-25370978-G-C

Variant names:

• chr15-25370978-G-C
• rs267604140
• NM_130839.5:c.1196C>G

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_130839.5(UBE3A):​c.1196C>G​(p.Pro399Arg) variant causes a missense change. 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: 32)
• Consequence: UBE3A NM_130839.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.74

Genes affected

UBE3A (HGNC:12496): (ubiquitin protein ligase E3A) This gene encodes an E3 ubiquitin-protein ligase, part of the ubiquitin protein degradation system. This imprinted gene is maternally expressed in brain and biallelically expressed in other tissues. Maternally inherited deletion of this gene causes Angelman Syndrome, characterized by severe motor and intellectual retardation, ataxia, hypotonia, epilepsy, absence of speech, and characteristic facies. The protein also interacts with the E6 protein of human papillomavirus types 16 and 18, resulting in ubiquitination and proteolysis of tumor protein p53. Alternative splicing of this gene results in three transcript variants encoding three isoforms with different N-termini. Additional transcript variants have been described, but their full length nature has not been determined. [provided by RefSeq, Jul 2008]

SNHG14 (HGNC:37462): (small nucleolar RNA host gene 14) This gene is located within the Prader-Willi critical region and produces a long, spliced paternally-imprinted RNA that initiates within a common upstream promoter region shared by the SNRPN (small nuclear ribonucleoprotein polypeptide N) and SNURF genes. This transcript serves as a host RNA for the small nucleolar RNA, C/D box 115 and 116 clusters. This RNA extends in antisense into the region of the ubiquitin protein ligase E3A gene (UBE3A), and is thought to regulate imprinted expression of UBE3A in the brain. This transcript undergoes extensive alternative splicing, and may initiate and terminate at multiple locations within this genomic region. The full-length structure of all splice forms is not determined. [provided by RefSeq, Mar 2017]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the UBE3A gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 44 curated pathogenic missense variants (we use a threshold of 10). The gene has 8 curated benign missense variants. Trascript score misZ: 6.9443 (above the threshold of 3.09). GenCC associations: The gene is linked to Angelman syndrome.
• BP4: Computational evidence support a benign effect (MetaRNN=0.19271082).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
UBE3A	NM_130839.5	c.1196C>G	p.Pro399Arg	missense_variant	Exon 6 of 13	ENST00000648336.2	NP_570854.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
UBE3A	ENST00000648336.2	c.1196C>G	p.Pro399Arg	missense_variant	Exon 6 of 13		NM_130839.5	ENSP00000497572.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Angelman syndrome Uncertain:1

Aug 15, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available"). ClinVar contains an entry for this variant (Variation ID: 458665). This variant has not been reported in the literature in individuals affected with UBE3A-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces proline, which is neutral and non-polar, with arginine, which is basic and polar, at codon 379 of the UBE3A protein (p.Pro379Arg). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.23
BayesDel_addAF	Uncertain	0.026	T
BayesDel_noAF	Benign	-0.20
CADD	Benign	22
DANN	Benign	0.94
DEOGEN2	Benign	0.30	.;.;.;.;.;.;.;.;.;T;.;.;.;T;T
Eigen	Benign	0.11
Eigen_PC	Uncertain	0.25
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.95	.;.;.;D;.;.;.;D;.;.;.;.;D;D;D
M_CAP	Benign	0.026	D
MetaRNN	Benign	0.19	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.65	T
MutationAssessor	Benign	1.4	.;.;.;.;.;.;.;.;.;L;.;.;.;L;.
PrimateAI	Uncertain	0.63	T
PROVEAN	Benign	-0.90	.;.;.;.;N;.;.;.;.;.;.;N;N;N;.
REVEL	Benign	0.17
Sift	Benign	0.11	.;.;.;.;T;.;.;.;.;.;.;T;T;T;.
Sift4G	Benign	0.52	.;.;.;.;.;T;.;.;.;.;.;.;.;T;.
Polyphen		0.70, 0.0030	.;P;.;.;.;P;.;P;.;B;.;.;.;B;.
Vest4		0.48, 0.62, 0.50, 0.54, 0.49, 0.57
MutPred		0.34		.;.;.;.;.;.;.;.;.;Gain of helix (P = 6e-04);.;.;.;Gain of helix (P = 6e-04);.;
MVP		0.26
MPC		1.0
ClinPred		0.35	T
GERP RS		5.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.17
gMVP		0.53

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs267604140; hg19: chr15-25616125;