DDB1

Chr 11AD

damage specific DNA binding protein 1

Also known as: DDBA, UV-DDB1, WHIKERS, XAP1, XPCE, XPE, XPE-BF

NCBI Gene: 1642 ENSG00000167986 UniProt: Q16531

The protein encoded by this gene is the large subunit (p127) of the heterodimeric DNA damage-binding (DDB) complex while another protein (p48) forms the small subunit. This protein complex functions in nucleotide-excision repair and binds to DNA following UV damage. Defective activity of this complex causes the repair defect in patients with xeroderma pigmentosum complementation group E (XPE) - an autosomal recessive disorder characterized by photosensitivity and early onset of carcinomas. However, it remains for mutation analysis to demonstrate whether the defect in XPE patients is in this gene or the gene encoding the small subunit. In addition, Best vitelliform mascular dystrophy is mapped to the same region as this gene on 11q, but no sequence alternations of this gene are demonstrated in Best disease patients. The protein encoded by this gene also functions as an adaptor molecule for the cullin 4 (CUL4) ubiquitin E3 ligase complex by facilitating the binding of substrates to this complex and the ubiquitination of proteins. [provided by RefSeq, May 2012]

Primary Disease Associations & Inheritance

White-Kernohan syndromeMIM #619426

170

ClinVar variants

Pathogenic / LP

1.00

pLI score· haploinsufficient

Active trials

Clinical Summary— DDB1

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Population Constraint (gnomAD)

Highly constrained gene — heterozygous loss-of-function variants are very rare in the population (pLI 1.00). One damaged copy is likely sufficient to cause disease.

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ClinVar Variants

16 Pathogenic / Likely Pathogenic· 133 VUS of 170 total submissions

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD

Dual constrained — LoF & missense intolerant

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.

0.24LOEUF

pLI 1.000

Z-score 6.19

OE 0.13 (0.08–0.24)

Highly constrained

Highly LoF-intolerant (top ~10% 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.

4.89Z-score

OE missense 0.47 (0.43–0.51)

313 obs / 668.5 exp

Constrained

Highly missense-constrained (top ~0.1%)

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.0.13 (0.08–0.24)

0≤0.351.4

Missense OE?Ratio of observed to expected missense variants. OE ≤ 0.6 = fewer missense variants than expected by chance.0.47 (0.43–0.51)

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.1.05

0≤1.21.6

LoF obs/exp: 8 / 59.5Missense obs/exp: 313 / 668.5Syn Z: -0.59