Double homeobox protein 4-like protein 4 (DUX4L4)

Double homeobox protein 4-like protein 4 (DUX4L4) is a member of the double homeobox protein family, characterized by the presence of two homeodomains, and is encoded within the D4Z4 macrosatellite repeat array in the subtelomeric region of chromosome 4q[5][7]. DUX4L4 is a paralog of DUX4 and shares high sequence similarity, but there is no direct evidence that DUX4L4 is actively transcribed or translated into protein under physiological conditions[5][7]. Experimental data suggest that a telomeric paralog may be transcribed in select haplotypes, but DUX4L4 itself is not typically expressed, and its biological function is unknown[5][7]. By analogy to DUX4, it likely encodes a transcription factor with DNA-binding capabilities mediated by its homeodomains, but direct roles in human physiology or pathology have not been demonstrated for DUX4L4. Unlike DUX4, which is implicated in facioscapulohumeral muscular dystrophy and some cancers, DUX4L4 is not a validated therapeutic target nor associated directly with any known disorders[3][4][7]. **Key caveats:** - DUX4L4 is often conflated with DUX4, which is a disease-relevant transcription factor, but they are distinct genetic loci[3][7]. - There is little evidence that DUX4L4 is an expressed gene in humans or that it encodes a functional protein; it is not recognized as a druggable/modifiable therapeutic target, nor does it have validated function or disease associations[5][7]. **Summary of rationale for is_incorrect=true:** DUX4L4 is frequently misattributed as a target based on homology to DUX4, but is not itself recognized as a functional, therapeutic, or disease-related protein. There is no evidence for clinical targeting, biomarker status, or drug development relevance. Its name and reported synonyms are technically correct, but its assignment as a target is not supported by the literature.

Other names

Double homeobox 4 like 4DUX4L4double homeobox protein 4-like protein 4D4Z4 repeat element geneDUX4-like