Liyanage M, Coleman A, du Manoir S, Veldman T, McCormack S, Dickson R B, Barlow C, Wynshaw-Boris A, Janz S, Wienberg J, Ferguson-Smith M A, Schröck E, Ried T
Diagnostic Development Branch, National Center for Human Genome Research, National Institutes of Health, Bethesda, Maryland 20892-4470, USA.
Nat Genet. 1996 Nov;14(3):312-5. doi: 10.1038/ng1196-312.
Murine models of human carcinogenesis are exceedingly valuable tools to understand genetic mechanisms of neoplastic growth. The identification of recurrent chromosomal rearrangements by cytogenetic techniques serves as an initial screening test for tumour specific aberrations. In murine models of human carcinogenesis, however, karyotype analysis is technically demanding because mouse chromosomes are acrocentric and of similar size. Fluorescence in situ hybridization (FISH) with mouse chromosome specific painting probes can complement conventional banding analysis. Although sensitive and specific, FISH analyses are restricted to the visualization of only a few mouse chromosomes at a time. Here we apply a novel imaging technique that we developed recently for the visualization of human chromosomes to the simultaneous discernment of all mouse chromosomes. The approach is based on spectral imaging to measure chromosome-specific spectra after FISH with differentially labelled mouse chromosome painting probes. Utilizing a combination of Fourier spectroscopy, CCD-imaging and conventional optical microscopy, spectral imaging allows simultaneous measurement of the fluorescence emission spectrum at all sample points. A spectrum-based classification algorithm has been adapted to karyotype mouse chromosomes. We have applied spectral karyotyping (SKY) to chemically induced plasmocytomas, mammary gland tumours from transgenic mice overexpressing the c-myc oncogene and thymomas from mice deficient for the ataxia telangiectasia (Atm) gene. Results from these analyses demonstrate the potential of SKY to identify complex chromosomal aberrations in mouse models of human carcinogenesis.
人类致癌作用的小鼠模型是理解肿瘤生长遗传机制的极其有价值的工具。通过细胞遗传学技术鉴定反复出现的染色体重排，可作为肿瘤特异性畸变的初步筛选测试。然而，在人类致癌作用的小鼠模型中，核型分析在技术上要求很高，因为小鼠染色体是近端着丝粒染色体且大小相似。使用小鼠染色体特异性涂染探针的荧光原位杂交（FISH）可以补充传统的显带分析。尽管FISH分析灵敏且特异，但一次只能可视化少数几条小鼠染色体。在此，我们应用一种我们最近开发的用于可视化人类染色体的新型成像技术，来同时辨别所有小鼠染色体。该方法基于光谱成像，在用差异标记的小鼠染色体涂染探针进行FISH后测量染色体特异性光谱。利用傅里叶光谱学、电荷耦合器件（CCD）成像和传统光学显微镜的组合，光谱成像能够在所有样本点同时测量荧光发射光谱。一种基于光谱的分类算法已被改编用于对小鼠染色体进行核型分析。我们已将光谱核型分析（SKY）应用于化学诱导的浆细胞瘤、过表达c-myc癌基因的转基因小鼠的乳腺肿瘤以及共济失调毛细血管扩张症（Atm）基因缺陷小鼠的胸腺瘤。这些分析结果证明了SKY在识别人类致癌作用小鼠模型中复杂染色体畸变方面的潜力。
