RAC4 is a Pseudogene
A recent publication by Kugler et al. (Gene 341, pp 189-197), entitled "Isolation and Characterization of Rac1 pseudogenes (psi1Rac1- psi4Rac1) in the Human Genome" describes four pseudogenes related to RAC1. The gene called RAC4 in this review article is identical to psi4Rac1. The official HGNC nomenclature for this pseudogene is RAC1P4. Note also that the Human Genome Nomenclature Committee (HGNC) has identified a total of five potential RAC1 pseudogene (RAC1P1-5). The large number of RAC1 pseudogenes, and their distribution over four human chromosomes, appears to be unique within the RAS superfamily.
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