However, certain factors may contribute to the development of this illness. Chromosomes and DNA control cell characteristics and growth. The causal role of toxic chemicals, viruses and other environmental agents has not been implicated. Activation of 'Oncogenes' An oncogene is a gene which is capable of initiating cancerous change. Oncogenes can be activated by damaged or altered chromosomes.
Oncogenes influence a cells structure and function.
This process creates a new gene called the bcr-abl gene. The bcr-abl gene is an oncogene. It is believed that the bcr-abl oncogene on the Ph chromosome causes the uncontrolled growth of leukaemia cells. Symptoms depend upon the stage of disease. The chronic phase may last for 3-6 years.