DDX42

Chr 17

DEAD-box helicase 42

Also known as: DDX42P, RHELP, RNAHP, SF3B8, SF3b125

NCBI Gene: 11325 ENSG00000198231 UniProt: Q86XP3

This gene encodes a member of the Asp-Glu-Ala-Asp (DEAD) box protein family. Members of this protein family are putative RNA helicases, and are implicated in a number of cellular processes involving alteration of RNA secondary structure such as translation initiation, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. Members of this family are believed to be involved in embryogenesis, spermatogenesis, and cellular growth and division. Two transcript variants encoding the same protein have been identified for this gene. [provided by RefSeq, Jul 2008]

Active trials

Pathogenic / LP

ClinVar variants

Pubs (1 yr)

3.3

Missense Z· constrained

0.13

LOEUF· LoF intolerant

Clinical Summary— DDX42

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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.

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.

0.13LOEUF

pLI 1.000

Z-score 6.08

OE 0.04 (0.02–0.13)

Highly constrained

Among the most LoF-intolerant genes (~top 3%)

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.

3.29Z-score

OE missense 0.60 (0.55–0.66)

329 obs / 544.9 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.0.04 (0.02–0.13)

0≤0.351.4

Missense OE?Ratio of observed to expected missense variants. OE ≤ 0.6 = fewer missense variants than expected by chance.0.60 (0.55–0.66)

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.0.94

0≤1.21.6

LoF obs/exp: 2 / 46.9Missense obs/exp: 329 / 544.9Syn Z: 0.60

0.4784th %ile

GOF

0.4480th %ile

LOF

0.70top 10%

The highest-scoring mechanism for this gene is loss-of-function (haploinsufficiency).

LOFprediction above median · LOEUF 0.13

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312. Mechanism ranking also informed by gnomAD constraint, ClinVar, and ClinGen data.