Larramendy M, Heiskanen M, Wessman M, Ritvanen A, Peltomäki P, Simola K, Kääriäinen H, von Koskull H, Kähkönen M, Knuutila S
Department of Medical Genetics, University of Helsinki, Finland.
Hum Genet. 1993 Mar;91(2):121-7. doi: 10.1007/BF00222711.
The Pallister-Killian syndrome (PKS) is characterized by tissue limited chromosomal mosaicism, i.e. the presence of a supernumerary metacentric chromosome [i(12p)] often confined to skin fibroblasts while the karyotype of cultured lymphocytes is normal. In the present study, chromosome painting by chromosomal in situ suppression (CISS) hybridization and interphase cytogenetic procedures employing biotinylated or digoxigenin labelled probes was carried out. These probes comprised a chromosome 12 specific library (LA 12NS01) and chromosome 12 centromere specific alpha-satellite (pSP12-1). They were used to analyse and quantify the presence of i(12p) in lymphocytes, granulocytes/monocytes, skin fibroblasts and buccal mucosal cells from five patients and one aborted fetus with PKS, and ten normal donors. CISS hybridization on mitotic skin fibroblasts reliably indicated the presence of i(12p) cells, even when metaphases of poor quality were included in the analysis. Two of the five patients showed i(12p) in a small proportion (< or = 0.5%) of the cultured lymphocytes too. The interphase cytogenetics procedure did not reveal the isochromosome in lymphocytes or granulocytes/monocytes in any of the patients. Two of the six patients had a twofold increase in the number of buccal mucosal cells with three hybridization signals over control values. However, for mucosal cells, methodological improvements are required. For cytogenetic diagnosis of PKS, cultured fibroblasts subjected to chromosome painting by CISS hybridization with a chromosome 12 specific library probe are recommended.
帕利斯特-基利安综合征（PKS）的特征是组织局限性染色体嵌合体，即存在一条额外的中着丝粒染色体[i(12p)]，通常局限于皮肤成纤维细胞，而培养的淋巴细胞核型正常。在本研究中，采用染色体原位抑制（CISS）杂交进行染色体描绘，并使用生物素化或地高辛配体标记的探针进行间期细胞遗传学操作。这些探针包括一个12号染色体特异性文库（LA 12NS01）和12号染色体着丝粒特异性α卫星（pSP12-1）。它们被用于分析和定量来自5例PKS患者、1例PKS流产胎儿以及10名正常供体的淋巴细胞、粒细胞/单核细胞、皮肤成纤维细胞和颊黏膜细胞中i(12p)的存在情况。即使在分析中纳入质量较差的中期分裂相，对有丝分裂的皮肤成纤维细胞进行CISS杂交也能可靠地显示i(12p)细胞的存在。5例患者中有2例在培养的淋巴细胞中也显示出小比例（≤0.5%）的i(12p)。间期细胞遗传学操作未在任何患者的淋巴细胞或粒细胞/单核细胞中发现等臂染色体。6例患者中有2例颊黏膜细胞中具有三个杂交信号的细胞数量比对照值增加了两倍。然而，对于黏膜细胞，需要改进方法。对于PKS的细胞遗传学诊断，建议使用12号染色体特异性文库探针通过CISS杂交对培养的成纤维细胞进行染色体描绘。
