Mefford H, van den Engh G, Friedman C, Trask B J
Department of Molecular Biotechnology, University of Washington, Seattle 98195, USA.
Hum Genet. 1997 Jul;100(1):138-44. doi: 10.1007/s004390050479.
Chromosomes sampled from seven human populations were analyzed by flow cytometry to survey normal variation in chromosome size. The populations include two African Pygmy groups, two Amerindian tribes, Druze, Khmer Cambodians, and Melanesians. Mitotic chromosomes were isolated from cultured cells and stained with Hoechst 33,258 and chromomycin A3. The relative DNA content and base-pair composition of each homolog was quantified by bivariate flow karyotyping. Significant variation in DNA content, ranging from 10-40%, was observed for chromosomes 1, 13-16, 19, 21, 22, and Y. The measurements for each population appeared to be a random sampling of the total set of 33 individuals for the majority of chromosomes. A few significant differences in the distributions of chromosomal DNA content were observed among the populations, however. The data, when combined with an earlier study of 33 unrelated individuals of unknown ethnic origin, provide a good representation of the variation in chromosome size among humans.
通过流式细胞术对来自七个人类群体的染色体进行分析，以调查染色体大小的正常变异情况。这些群体包括两个非洲俾格米人群体、两个美洲印第安部落、德鲁兹人、高棉柬埔寨人以及美拉尼西亚人。从培养细胞中分离出有丝分裂染色体，并用 Hoechst 33,258 和嗜铬霉素 A3 进行染色。通过双变量流式核型分析对每个同源染色体的相对 DNA 含量和碱基对组成进行定量。在 1 号、13 - 16 号、19 号、21 号、22 号染色体以及 Y 染色体上观察到 DNA 含量存在显著变异，范围在 10% - 40%之间。对于大多数染色体而言，每个群体的测量结果似乎是对 33 个个体的整个集合的随机抽样。然而，在不同群体之间观察到了一些染色体 DNA 含量分布的显著差异。这些数据与早期对 33 名未知种族来源的无关个体的研究相结合，很好地呈现了人类染色体大小的变异情况。
