Background: Structural maintenance of chromosomes (SMC) proteins are part of the cohesin and condensin multisubunit complexes that play a critical role in chromosome organization, segregation, gene regulation, and DNA repair. The core condensin complex includes a heterodimer of SMC2 and SMC4 that functions to create positively supercoiled loops for chromatin condensation and metaphase chromatid shaping. A function for condensin in the DNA damage checkpoint response and gene repression has also been suggested.