Engels Hartmut, Ehrbrecht Antje, Zahn Susanne, Bosse Kristin, Vrolijk Hans, White Stefan, Kalscheuer Vera, Hoovers Jan M N, Schwanitz Gesa, Propping Peter, Tanke Hans J, Wiegant Joop, Raap Anton K
Institute of Human Genetics, University of Bonn, Wilhelmstrasse 31, D-53111 Bonn, Germany.
Eur J Hum Genet. 2003 Sep;11(9):643-51. doi: 10.1038/sj.ejhg.5201028.
Cryptic subtelomeric chromosome rearrangements play an important role in the aetiology of mental retardation, congenital anomalies, miscarriages and neoplasia. To facilitate a comprehensive molecular-cytogenetic analysis of these extremely gene-rich and mutation-prone chromosome regions, novel multicolour fluorescence in situ hybridisation (FISH) techniques are being developed. As yet, subtelomeric FISH methods have either had limited multiplicities, making it necessary to perform many hybridisations per patient, or a limited scope of analysable chromosome mutation types, thus not detecting some aberration types such as pericentric inversions or very small aberrations. COBRA (COmbined Binary RAtio) labelling is a generic multicolour FISH technique that combines ratio and combinatorial labelling to attain especially high multiplicities with few fluorochromes. The Subtelomere COBRA FISH method ("S-COBRA FISH") described here detects efficiently all 41 BAC and PAC FISH probes necessary for a complete subtelomere screening in only two hybridisations. It was applied to the analysis of 10 cases with known and partially known aberrations and successfully detected balanced and unbalanced translocations, deletions and an unbalanced pericentric inversion in a mosaic situation. The ability of S-COBRA FISH to efficiently detect all types of balanced and unbalanced subtelomeric chromosome aberrations makes it the most comprehensive diagnostic procedure for human subtelomeric chromosome regions described to date.
隐匿性亚端粒染色体重排在智力发育迟缓、先天性畸形、流产和肿瘤形成的病因学中起着重要作用。为了便于对这些基因极其丰富且易于发生突变的染色体区域进行全面的分子细胞遗传学分析，新型多色荧光原位杂交（FISH）技术正在研发中。到目前为止，亚端粒FISH方法要么多样性有限，导致每个患者需要进行多次杂交，要么可分析的染色体突变类型范围有限，因此无法检测到某些畸变类型，如臂间倒位或非常小的畸变。COBRA（组合二元比率）标记是一种通用的多色FISH技术，它结合了比率标记和组合标记，用少量荧光染料就能实现特别高的多样性。本文所述的亚端粒COBRA FISH方法（“S-COBRA FISH”）仅通过两次杂交就能高效检测出完整亚端粒筛查所需的所有41个BAC和PAC FISH探针。它被应用于分析10例已知和部分已知畸变的病例，并成功检测到了平衡和不平衡易位、缺失以及一例嵌合状态下的不平衡臂间倒位。S-COBRA FISH能够高效检测所有类型的平衡和不平衡亚端粒染色体重排，使其成为迄今为止所描述的针对人类亚端粒染色体区域最全面的诊断方法。
