Thick J, Mak Y F, Metcalfe J, Beatty D, Taylor A M
Department of Cancer Studies, University of Birmingham, UK.
Leukemia. 1994 Apr;8(4):564-73.
A t(X;14)(q28;q11) translocation was present for many years in T cells in two patients with ataxia telangiectasia (A-T), who subsequently developed T-prolymphocytic leukemia. We describe here the relationship between the translocation breakpoints in these patients with respect to two recently described genes, c6.1A and c6.1B, on Xq28 which are transcribed in opposite directions from the same CpG island. In our first patient, the Xq28 breakpoint disrupts the c6.1A gene which is consequently transcribed as a fusion mRNA with the TCR C alpha chain gene. In the second case, the Xq28 breakpoint lies within the adjacent gene c6.1B, and c6.1A is not transcribed. We show that the c6.1B gene is transcribed in both of our patients. c6.1B may be important in the initial clonal proliferation of T lymphocytes which commonly precedes transformation to T-PLL in ataxia telangiectasia patients. The same gene may also be involved in the development of T-PLL in the non-A-T population.
在两名患有共济失调毛细血管扩张症（A-T）的患者的T细胞中，一种t(X;14)(q28;q11)易位存在多年，这两名患者随后发展为T-原淋巴细胞白血病。我们在此描述这些患者中易位断点之间的关系，该关系涉及Xq28上最近描述的两个基因c6.1A和c6.1B，它们从同一个CpG岛以相反方向转录。在我们的首例患者中，Xq28断点破坏了c6.1A基因，因此该基因作为与TCR Cα链基因的融合mRNA进行转录。在第二例中，Xq28断点位于相邻基因c6.1B内，且c6.1A未转录。我们发现c6.1B基因在我们的两名患者中均有转录。c6.1B可能在T淋巴细胞的初始克隆增殖中起重要作用，在共济失调毛细血管扩张症患者中，这种增殖通常先于向T-PLL的转化。同一基因可能也参与非A-T人群中T-PLL的发生发展。
