The cells undergo a typical cyclical pattern consisting of interphase and mitosis. The division phase or mitosis involves an important phase dependent on the centromere splitting or separation. This phase is known as anaphase. It involves splitting of the centromere to move the daughter chromatids towards the opposite poles. Certain factors play a crucial role in the splitting of the centromeres. The initiation of the centromere splitting first requires an anaphase-promoting complex. This complex involves an inhibitory chaperone known as securin. The APC/C cyclosome degrades three main factors such as securin, S and M cyclins. The degradation of securin releases a protease known as separase which in turn cleaves the cohesins. The cohesins bond the sister chromatids intact and allow non-homologous centromere coupling. However, the cleavage of the cohesin happens during anaphase. It further accelerates the centromere splitting and sister chromatid separation. The centromere splitting may be either horizontal or longitudinal (vertical). Normally the centromere divides longitudinally. However, the centromere splitting may accompany errors. A common error occurs when the centromere divides horizontally. Two isochromosomes arise due to incorrect centromere splitting. These isochromosomes have genetically identical arms. The isochromosomes may have duplication on one arm and deletion on the other arm.