GTPase-activating proteins (GAPs) accelerate the intrinsic rate of GTP hydrolysis of Ras-related proteins, resulting in downregulation of their active form. ARHGAP36 (Rho GTPase activating protein 36) is a 547 amino acid protein that contains one Rho-GAP domain. Conserved in chimpanzee, dog, cow, mouse and rat, ARHGAP36 exists as five alternatively spliced isoforms and is encoded by a gene that maps to human chromosome Xq26.1. Chromosome X consists of nearly 153 million base pairs encoding approximately 1,000 genes. More than one copy of the X chromosome with a Y chromosome causes Klinefelter's syndrome. A single copy of X alone leads to Turner's syndrome. More than 2 copies of the X chromosome, in the absence of a Y chromosome, is known as Triple X syndrome. Color blindness, hemophilia, and Duchenne muscular dystrophy are X chromosome-linked conditions that affect males more frequently because males carry a single X chromosome.