Final answer:
The 15;17 chromosomal translocation signifies acute promyelocytic leukemia, leading to the malfunction of the retinoic acid receptor in the affected cells due to the fusion of RARA with the PML gene, causing white blood cells to proliferate uncontrollably.
Step-by-step explanation:
The 15;17 chromosomal translocation found in cytogenetic studies of a patient presenting with severe fatigue, exertional dyspnea, and fever often signifies acute promyelocytic leukemia (APL). In this type of leukemia, the most likely malfunctioning protein in the affected cells due to this translocation is the retinoic acid receptor (C. Retinoic acid receptor).
This translocation results in the fusion of the gene for retinoic acid receptor alpha (RARA) on chromosome 17 with the promyelocytic leukemia (PML) gene on chromosome 15, leading to the production of an abnormal protein that interferes with the normal differentiation of white blood cells. These cells fail to mature and instead proliferate uncontrollably, which is the hallmark of this type of leukemia.
While epidermal growth factor receptor (EGFR) is significant in cellular proliferation and is often associated with cancer, its dysfunction is not typically related to the specific translocation (15;17) mentioned in the question. Therefore, the correct answer to the question is C. Retinoic acid receptor malfunctioning in the cells with this chromosomal translocation.