Chromosomal Analysis
In the case of acute lymphoblastic leukemia (ALL), chromosome analysis, known as karyotyping as well, is indicated. The primary reason why it is required is its ability to help clinicians detect chromosome anomalies. The full knowledge and analysis of these abnormalities are both essential to diagnose ALL. No test preparation is needed prior to the procedure, which usually occurs only if there is an issue with a pregnancy screening test or if there are signs typically associated with a disorder caused by a chromosomal abnormality. American Cancer Society (2018) reports that chromosome changes, which lead to ALL, are translocations, the most common of which is the Philadelphia chromosome. It is “a swap of DNA between chromosomes 9 and 22, abbreviated as t(9;22)” (American Cancer Society, 2018, para. 7).
Other chromosome abnormalities causing ALL may include translocations between chromosomes 4 and 11, 8 and 14, as well as deletions and inversions. Deletions refer to the genetic make-up, where part of a chromosome is lost, while inversions are the DNA rearrangement within a chromosome. Chromosome analysis is crucial to determine whether a patient has acute lymphoblastic leukemia and, if so, which subtype is based on the identified chromosome changes. Apart from analyzing chromosome abnormalities present in patients with ALL, the purpose of this paper is to investigate the disorder’s origin, including primary causes and the process of gene mutations.
Causes of the Disorder
In regards to the causes of ALL, the disorder occurs when there are genetic mutations in a bone marrow cell. Due to these abnormalities, a cell’s DNA does not have the necessary instructions as to what it should do. Each time a cell reproduces and divides into two, it creates two identical copies of chromosomes. Since this process is rather complex, certain issues can occur, including errors known as mutations. When it comes to cancer, these changes turn on oncogenes responsible for cell growth and turn off tumor suppressor genes, which unsettles the balance between cell division and death.
In the case of cancer, the changes in the genetic material lead to cells growing and dividing continuously instead of following a set timeline and pattern of doing a specific task and dying. Acute lymphoblastic leukemia is caused by cells dividing at a rate that interferes with the normal process of blood cell production. As a result of these abnormalities in cell proliferation, the bone marrow makes cells not mature enough to function properly, leading to them becoming lymphoblasts, which are essentially white blood cells mutated to cause leukemia. The reason behind ALL is “recurrent chromosomal aberrations including hyperdiploidy and chromosomal dislocations” (Hein et al., 2020, p. 161). It is yet unclear what exactly causes the DNA mutations leading to ALL, to begin with.
Thus, it is apparent that the definite etiology of the disorder is unknown. However, Karamikhah and Karimzadeh (2020) argue that the following factors might be involved: exposure to vital pathogens, genetic predisposition, and in utero exposure to chemicals and radiation. Other determinants may be “environmental factors such as exposure to electromagnetic fields, pesticides, maternal use of alcohol, and cigarette smoking,” as well as “drugs such as etoposide and doxorubicin” (Karamikhah & Karimzadeh, 2020, p. 2). Although the identification of these risk factors does not explain the causes for mutations leading to ALL, they are helpful during the initial stages of diagnosis.
Disorder Origin: Considerations for Practice and Patient Education
In order to fully understand the disorder, it is important to analyze its possible origin pathways. Jimenez-Morales et al. (2017) note that certain ALL cases follow a Mendelian inheritance pattern. In addition, this type of cancer should be considered multifactorial, “a complex pattern of inheritance, where polymorphisms in low-penetrance genes involved in DNA repair, in response to xenobiotics, in the immune system and regulatory genes predispose to the development of the disease” (Jimenez-Morales et al., 2017, p. 16). This is the origin of the disorder, which is crucial to examine in order to further investigate possible causes, risk factors, symptoms, potential treatments, and prognoses.
As for considerations for practice, the primary point of focus should be the fact that ALL occurs mainly in children. Thus, clinicians have to constantly remain in contact with the family in relation to any medical decisions. This can be especially hard since parents are usually emotionally vulnerable after finding out about their child’s diagnosis. A doctor can raise suspicion regarding the possibility of gene mutations leading to ALL after examining a patient’s medical history and extensively interviewing parents. This process ensures there is substantial information about existing risk factors that might have led to the child developing the disorder, including radiation and cancer-causing chemicals exposure, genetic syndromes, and so on.
However, other crucial prognostic factors include “the presence of MLL rearrangement, hyperleukocytosis, age less than three to six months, and poor response to prednisone prophase” (Lee & Cho, 2017, p. 133). To ensure there is no miscommunication and patients make informed medical decisions, the medical staff has to educate patients. They or their caretakers have to have knowledge of laboratory testing, risk factors, prognosis, symptoms, possible treatments and their side effects, disorder incidence, and statistics regarding the risk of remission.
Gene Mutation of the Disease
There are people who develop a certain type of cancer due to the DNA mutations they have inherited from their parents, which substantially increases their chances of getting sick. However, when it comes to acute lymphoblastic leukemia, this is not a common occurrence. Inherited mutations are only a concern in cases where patients have existing genetic syndromes listed as some of the possible risk factors for developing ALL.
Thus, it is evident that DNA changes associated with the disorder are usually acquired during a patient’s lifetime. For instance, one can get ill due to exposure to radiation or cancer-causing chemicals. In other instances, mutations are a result of random events within a cell which do not have a specific external cause. As these changes build up with age, it is understandable why older people are at a much higher risk of developing ALL, at least among the adult population.
As for how the mutations occur, as mentioned earlier, there are no definite causes. However, scientists now understand that the disorder itself develops from recurrent genetic changes, which block preceding B- and T-cell differentiation and simultaneously increase the pace of cell proliferation. As a result, the body accumulates malignant, immature lymphoid cells either in the bone marrow or in peripheral blood. Gene abnormalities might occur as a result of chromosomal translocations generating fusion proteins, tumor suppressor genes deactivating, function mutations expanding, and oncogene activating.
References
American Cancer Society. (2018). What causes acute lymphocytic leukemia (ALL)? Cancer. Web.
Hein, D., Borkhardt, A., & Fischer, U. (2020). Insights into the prenatal origin of childhood acute lymphoblastic leukemia. Cancer and Metastasis Reviews, 39, 161-171. Web.
JimĂ©nez-Morales, S., Hidalgo-Miranda, A., & RamĂrez-Bello, J. (2017). Acute lymphoblastic leukemia: a genomic perspective. BoletĂn MĂ©dico Del Hospital Infantil de MĂ©xico (English Edition), 74(1), 13–26. Web.
Karamikhah, R., & Karimzadeh, I. (2020). Acute lymphoblastic leukemia in children: A short review. Trends in Pharmaceutical Sciences, 6(4), 283-296. Web.
Lee, J. W., & Cho, B. (2017). Prognostic factors and treatment of pediatric acute lymphoblastic leukemia. Korean Journal of Pediatrics, 60(5), 129–137. Web.