Acute Lymphocytic Leukemia - Symptoms

Causes

The causes of the disease are not known, but researchers believe that ALL develops from a combination of genetic, biologic, and environmental factors.

Genetic Translocations

Up to 65% of leukemias contain genetic rearrangements, called translocations, in which some of the genetic material (genes) on a chromosome may be shuffled or swapped between a pair of chromosomes.

• The most common genetic translocation in ALL is the Philadelphia (Ph) chromosome where DNA is swapped between chromosomes 9 and 22 [t(9:22)]. It occurs in about 20 - 30% of adults and 3 - 5% of children with ALL.
• Another common translocation in ALL is t(12;21), which is referred to as TEL-AML1 fusion. It occurs in about 20% of patients with ALL.

Review Date: 01/27/2011
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org).

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