Cancer Genetics: Breast Cancer
Cancers are among the deadliest diseases on the planet due to the poor prognosis, especially after a late diagnosis that postponed the necessary treatment. According to Apostolou and Fostira (2013), breast cancer is characterized by breast cells becoming abnormal multiplying at an unusual rate to form malignant tumors; majorly, the neoplasm is attributed to many factors including genetic inheritance and mutations that affect a variety of genes. Further, Apostolou et al. (2015) explain that BRCA1 and BRCA2 genes account for 5-10% of all the hereditary cases of breast cancer across the planet regardless of the women's socioeconomic statuses; additionally, mutations in these genes enhance the risk of neoplasm development by 82%.
Similarly, the prevalence of breast cancer is high with one in eight women developing the condition at one point in life. Some of the risk factors for cancer include reproductive, menstrual, and hormonal history, sedentary lifestyle, age, obesity, exposure to ionizing radiations, excessive intake of alcohol, and, most importantly, the presence of benign breast disease as well as the familial history of the neoplasm (Apostolou & Fostira, 2013). Basically, hereditary factors that involve the mutation of appropriate genes play a critical role in the development of breast cancer due to the massive influence of molecular genetics.
The principles of heredity, namely meiosis, and mitosis as the processes of cell division, directly apply to the issue of breast cancer in women. According to Dominguez-Brauer et al. (2015), the mammalian process of cell division is driven by protein activation and deactivation to regulate the phases of the cell cycle. Briefly, the cell cycle comprises five phases: G0, G1, S or the synthesis phase, G2, and most importantly, the M or mitosis (Yanagida, 2014). Cells in the G0 phase are quiescent or resting; some of the cells in the body remain in this phase for their entire life. External factors of growth stimulate the resting cells to enter the G1 phase, which entails the synthesis of proteins and DNA molecules for replication in the S phase (Dominguez-Brauer et al., 2015).
In the G2 phase, the replication of DNA molecules is monitored for fidelity as the cells await entering the mitotic phase; during mitosis, cytokinesis occurs resulting in the division of the primary cell into two daughter cells (Yanagida, 2014). Primarily, cell division which occurs by either mitosis or meiosis plays a critical role in determining the occurrence of breast cancer in women across their lifespan regardless of their race or socioeconomic status.
To ensure that only healthy breast cells proliferate during the cell cycle, several factors are involved in moderating the process of cell division; it is at this point that breast cancer is determined since the failure to regulate the process results in malignancies. The arrest of the cell cycle allows for the repair of the defects in the replication of DNA through mitotic catastrophe, apoptosis, and senescence among other strategies to avoid passing unwanted traits to daughter cells (Dominguez-Brauer et al., 2015).
The checkpoint at the G1-S phase restricts the entry of damaged DNA molecules into the S phase of the cycle until the risks or damages are successfully removed. Similarly, the intra-S checkpoints slow down the replication of DNA during the S phase with the primary aim of minimizing replication errors (Dominguez-Brauer et al., 2015). Moreover, the checkpoint between the G2 and M phases prevents the premature entry of cells into mitosis to minimize the missegregation of chromosomes.
Basically, these and many other checkpoints mitigate the likelihood of genomic instability during the cell cycle. However, any failure in the process of mitosis results in unscheduled proliferation of cells without any regulation leading to the development of malignancies in the breast (Dominguez-Brauer et al., 2015). Basically, breast cancer is coupled with the rapid division of cells in the breast tissue leading to the subsequent development of malignant tumors. The altered genes can be passed to the offspring in the process of meiosis leading to the inheritance of breast cancer oncogenes. Therefore, many people whose parents are carriers of these cancerous genes are likely to inherit them leading to a high probability of developing the neoplasm.
Molecular Genetics Principles
The principles of molecular genetics applicable to breast cancer include transcription, translation, and replication. As earlier stated, the cell cycle entails the replication of DNA material during the process of cell division in meiosis and mitosis; when these two types of cell division occur, various checkpoint measures are executed to control the integrity of the entire cycle (Dominguez-Brauer et al., 2015). However, replication of the DNA material is uncontrolled in the affected breast tissues in the presence of breast cancer. Also, translation and transcription apply to breast cancer since the development of neoplasm is a consequence of malfunctions in the process of DNA repair through mutations, deletions, insertions, and base replacements among others (Davis, & Lin, 2011).
For instance, mutations may occur during the transcription of translation processes resulting in inappropriately high levels of the mechanisms of DNA repairs that sometimes suppress the control of cell replication. Consequently, the defects in the repair of DNA molecules may affect the BRCA1 genes leading to the development of breast cancer (Davis, & Lin, 2011). Fundamentally, transcription and translation have a significant influence on the genetic factors that predispose women to breast cancer.
Further, researchers have established the role of DNA replication in the development of neoplasms including those of the breast in women. According to Davis and Lin (2011), replication stress is the primary hallmark of the pre-cancerous cells; this stress may occur in response to hormonal or many other factors that stimulate replication. Primarily, chromosomal abnormalities may accumulate when the replication stress is high leading to the subsequent increase in the number of oncogenes to cause breast cancer (Davis, & Lin, 2011).
Additionally, Vassilev and DePamphilis (2017) explain that DNA replication is involved in the accumulation of genetic mutations occurring during the proliferative phase of the stem cells to develop and maintain human tissues and organs. Some of the mutations occur due to DNA replication errors thus initiating carcinogenesis and the subsequent destabilization of the genome to promote aneuploidy through excessive chromatid missegregation and duplication (Vassilev & DePamphilis, 2017). Eventually, cell neoplasia becomes a consequence of replication abnormalities; as such, replication, transcription, and translation are significant principles alluded to the occurrence of breast cancer in women.
Principles of Variation
The fundamental mutations related to breast cancer are those which affect the repairing process of DNA material, population genetics, and most importantly, multifactorial traits. Mutations, which occur through deletion and insertions among others have a significant impact on how DNA materials replicate and are repaired; once the mutations occur, oncogenes are formed leading to the alterations of the typical replication processes in the cell cycle (Dominguez-Brauer et al., 2015). Consequently, the alterations in the DNA repairing process as a result of the mutations contribute to the development of breast cancer oncogenes, which increases the risk of the development of this neoplastic condition in women. Through population genetics, some cancerous traits are transmitted from one generation to the other explaining the inheritance nature of breast neoplasms.
The multifactorial traits that play a role include not only the genetic inheritance but also exposure to environmental factors such as ionizing radiation, tobacco, alcohol, occupational chemicals, and lifestyle issues including unhealthy eating and sedentary lifestyles (Davis, & Lin, 2011). Therefore, germline mutations are inherited from parents by offspring, a phenomenon that leads to breast cancer inheritance in most of the populations despite the multifactorial traits playing a significant role in causing the condition.
Many deaths are associated with breast cancer in women, majorly in cases related to delayed diagnosis and treatment of the condition. Early diagnosis helps not only in the treatment of the breast neoplasm but also in dispelling of the associated fears (Eid & Nahon-Serfaty, 2015). Additionally, genetic testing has become a significant issue of concern not only in the United States but also in other parts of the planet determining the history of the family to a variety of cancers as well as the risk of developing the condition in future generations through inheritance. Breast cancer screening and genetic testing are complicated by a myriad of ethical challenges that should be addressed as a matter of urgent concern to facilitate the process of curbing the neoplastic menace (Eid & Nahon-Serfaty, 2015).
For instance, individuals should be tested only after giving informed consent. Also, confidentiality should be upheld; besides, consent should be obtained after clients have received all the information concerning the testing and screening of cancer as well as the associated repercussions.
Individuals who test positive for the mutations associated with breast cancer face dilemmas concerning their decisions on whether to have children who are likely to inherit the neoplasm; also, they are left pondering on whether or not to inform their relatives. Therefore, genetic counselors and other health professionals should work with their clients to address these and many other ethical challenges to curb the issue of breast cancer.
Breast cancer is a common condition caused by multifactorial issues that range from genetic abnormalities to environmental issues such as exposure to chemicals, unhealthy lifestyles, and so forth. During the cell division process, abnormalities may occur due to mutations resulting in the lack of control of the cell cycle. As a result, breast tissue cells may start proliferating at high rates leading to the development of malignancies. Translation, transcription, and replication are majorly associated with the development of cancer whenever abnormalities occur.
Although early diagnosis, which can be aided by genetic testing and screening of the condition, is essential in improving the prognosis of the neoplasm, ethical challenges complicate the efforts to address this menace. However, the collaborative handling of ethical issues and involvement of patients in their own care will likely have a positive impact on addressing the ethical challenges.