Arranz E, López J L, Robledo M, Martínez B, Escudero A, Benítez J
Department of Genetics, Fundación Jiménez Díaz, Madrid, Spain.
Cancer Genet Cytogenet. 1996 Apr;87(2):172-5. doi: 10.1016/0165-4608(95)00290-1.
Acute promyelocytic leukemia (APL) is a specific type of acute myelogenous leukemia characterized by a typical morphology and by a translocation between chromosomes 15 and 17, t(15;17)(q22;q21). Because this translocation is not found in other subtypes of acute myelogenous leukemias, it has become an important marker in the diagnosis and treatment of APL. Here we report a case with apparent absence of t(15;17) cells by cytogenetic techniques at diagnosis. At relapse, a metaphase FISH analysis (not dependent on chromosomal quality), followed by G-banding, was performed. t(15;17) was detected in 60% of the metaphases. In 30% of metaphases, an additional t(6;17) was detected involving the other chromosome 17 at band q21. In parallel, a molecular study (using the Southern blotting technique) was carried out and a single molecular rearrangement of the RAR-alpha gene was detected implying that RAR-alpha was not rearranged in the t(6;17) translocation.
急性早幼粒细胞白血病（APL）是急性髓系白血病的一种特殊类型，其特征为典型的形态学表现以及15号和17号染色体之间的易位，即t(15;17)(q22;q21)。由于这种易位在急性髓系白血病的其他亚型中未被发现，它已成为APL诊断和治疗的重要标志物。在此我们报告一例在诊断时通过细胞遗传学技术明显未检测到t(15;17)细胞的病例。复发时，进行了中期荧光原位杂交分析（不依赖染色体质量），随后进行G显带分析。在60%的中期相中检测到t(15;17)。在30%的中期相中，检测到另一种涉及17号染色体另一条q21带的t(6;17)。同时，进行了一项分子研究（使用Southern印迹技术），检测到视黄酸受体α（RAR-α）基因的单一分子重排，这意味着RAR-α在t(6;17)易位中未发生重排。
