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为了探讨中国人Ｔ细胞受体（ＴＣＲ）δ基因的Ｖ－Ｄ－Ｊ结合部顺序（Ｎ顺序）的组成，及其在急性淋巴细胞白血病（ＡＬＬ）患者中的重组规律，应用聚合酶链反应（ＰＣＲ）对４６例ＡＬＬ标本进行了ＴＣＲδ基因重排的研究，发现１６例患者出现Ｔ细胞受体δ基因不完全重排，其中１３例为Ｖδ２－（Ｄ）－Ｄδ３重排，３例为Ｖδ２－（Ｄ）－Ｄδ３合并Ｄδ２－Ｄδ３重排。进而应用ＤＮＡ直接测序技术，对这１６例ＡＬＬ标本ＴＣＲδ基因重排结合部进行了分析，证实由于Ｖδ２或Ｄδ２的３＇端和Ｄδ３的５＇端碱基缺失、部分Ｄδ１或Ｄδ２顺序存在、Ｎ顺序的插入以及未发生缺失的Ｖδ２，Ｄδ２或Ｄδ３编码顺序端Ｐ核昔酸的非随机插入，使得每例患者的结合部顺序均存在高度个体特异性。此外，对Ｎ顺序碱基成份的分析表明，其脱氧鸟嘌呤和脱氧胞嘧啶含量大于７０％，而脱氧腺嘌呤和脱氧胸腺嘧啶小于３０％，说明碱基插入并非完全随机。本文结果提示ＴＣＲδ基因重排是淋巴细胞发育中的一个早期事件，其结合部顺序的测定，可作为检测ＡＬＬ患者微小残留病变的特异性克隆标志。
To investigate the composition of the V-D-J binding sequence (N sequence) of the Chinese T-cell receptor (TCR) δ gene and its recombination pattern in patients with acute lymphoblastic leukemia (ALL), polymerase chain reaction was used. (46) TCRδ gene rearrangement studies were performed on 46 ALL specimens and found that 16 patients had incomplete rearrangement of T cell receptor δ gene, of which 13 cases were Vδ2-(D)-Dδ3 rearrangement, and 3 cases were. Vδ2-(D)-Dδ3 incorporates a Dδ2-Dδ3 rearrangement. Then, DNA direct sequencing technology was used to analyze the rearrangement of TCRδ gene in these 16 ALL specimens. It was confirmed that the 3′ end of Vδ2 or Dδ2 and the 5′ end of Dδ3 were missing, and part of Dδ1 or Dδ2 existed in order. Sequential insertions and non-random insertions of Vδ2, Dδ2, or Dδ3 coding sequences without deletions resulted in a high degree of individual specificity in the binding sequence of each patient. In addition, analysis of the N-sequential base composition showed that the deoxyguanine and deoxycytidine content was greater than 70%, while deoxyadenosine and deoxythymidine were less than 30%, indicating that the base insertion was not completely random. The results of this study suggest that TCRδ gene rearrangement is an early event in lymphocyte development. The determination of the binding site sequence can be used as a specific clone marker for the detection of minimal residual disease in ALL patients.