UBE3B

Chr 12AR

ubiquitin protein ligase E3B

Also known as: BPIDS, KOS

NCBI Gene: 89910 ENSG00000151148 UniProt: Q7Z3V4

The modification of proteins with ubiquitin is an important cellular mechanism for targeting abnormal or short-lived proteins for degradation. Ubiquitination involves at least three classes of enzymes: E1 ubiquitin-activating enzymes, E2 ubiquitin-conjugating enzymes, and E3 ubiquitin-protein ligases. This gene encodes a member of the E3 ubiquitin-conjugating enzyme family which accepts ubiquitin from an E2 ubiquitin-conjugating enzyme and transfers the ubiquitin to the targeted substrates. A HECT (homology to E6-AP C-terminus) domain in the C-terminus of the longer isoform of this protein is the catalytic site of ubiquitin transfer and forms a complex with E2 conjugases. Shorter isoforms of this protein which lack the C-terminal HECT domain are therefore unlikely to bind E2 enzymes. Alternatively spliced transcript variants encoding distinct isoforms have been identified for this gene. [provided by RefSeq, Jul 2012]

Primary Disease Associations & Inheritance

Kaufman oculocerebrofacial syndromeMIM #244450

572

ClinVar variants

Pathogenic / LP

0.00

pLI score

Active trials

Clinical Summary— UBE3B

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Gene-Disease Validity (ClinGen)

oculocerebrofacial syndrome, Kaufman type · ARDefinitive

Definitive — sufficient evidence for diagnostic panels

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Population Constraint (gnomAD)

Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.

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ClinVar Variants

78 Pathogenic / Likely Pathogenic· 222 VUS of 572 total submissions

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD

Moderate LoF intolerance

LoF Constraint?LOEUF (Loss-of-function Observed/Expected Upper bound Fraction) is the upper bound of the 90% CI for LoF OE — the preferred gnomAD v4 metric. Lower = more intolerant to LoF. LOEUF < 0.35 = highly constrained.

0.55LOEUF

pLI 0.000

Z-score 4.47

OE 0.39 (0.28–0.55)

Moderately constrained

More LoF-intolerant than ~75% of genes

Missense Constraint?Missense Z-score: standard deviations fewer missense variants observed vs. expected. Z > 3.09 (p < 0.001) = gene does not tolerate missense variation. OE missense < 0.6 is also considered constrained.

1.36Z-score

OE missense 0.85 (0.79–0.91)

539 obs / 635.4 exp

Tolerant

Mild missense constraint

Observed / Expected Ratios?Shaded band = 90% confidence interval. Vertical tick = point estimate. Grey threshold line = gnomAD constraint cutoff for that variant class.

LoF OE?Ratio of observed to expected LoF variants. Upper CI bound (LOEUF) ≤ 0.35 = strong LoF constraint signal.0.39 (0.28–0.55)

0≤0.351.4

Missense OE?Ratio of observed to expected missense variants. OE ≤ 0.6 = fewer missense variants than expected by chance.0.85 (0.79–0.91)

0≤0.61.4

Synonymous OE?Control metric — synonymous variants are largely neutral and expected near OE = 1.0. Significant deviation may indicate annotation issues.0.93

0≤1.21.6

LoF obs/exp: 24 / 62.0Missense obs/exp: 539 / 635.4Syn Z: 0.86