Müller S, O'Brien P C, Ferguson-Smith M A, Wienberg J
Department of Pathology, University of Cambridge, UK.
Cytogenet Cell Genet. 1997;78(3-4):260-71. doi: 10.1159/000134669.
We used fluorescence in situ hybridisation to delineate the homology between the human karyotype and those of two lemur species (Eulemur macaco macaco and E. fulvus mayottensis). Human and lemur chromosome-specific probes were established by bivariate fluorescence-activated flow sorting (FACS) and subsequent degenerate oligonucleotide-primed PCR (DOP-PCR). Reciprocal painting of human probes to lemur chromosomes and vice versa allowed a detailed analysis of the interchromosomal rearrangements that had occurred during the evolution of these species. The results indicate that the genomes of both species have undergone only a few translocations during more that 45 million years of lemur and human evolution. The synteny of homologs to human chromosomes 3, 9, 11, 13, 14, 17, 18, 20, 21, X, and Y was found to be conserved in the two lemur species. Taking non-primate mammals as the outgroup for primates, ancestral conditions for various primate chromosomes were identified and distinguished from derived forms. Lemur chromosome painting probes were also used for cross-species hybridization between the two lemur species. The results support an earlier assumption, made on the basis of chromosome banding, that the karyotypes of the two species have evolved exclusively by Robertsonian transformations. All probes derived from E. f. mayottensis chromosomes specific for homologs involved in rearrangements in E. m. macaco exclusively painted entire chromosome arms. The results further indicate that E. f. mayottensis most probably has a more ancestral karyotype than E. m. macaco. Probes derived from prosimians will be useful in comparing the karyotypes of other lower primates, which will improve our understanding of early primate genome evolution.
我们使用荧光原位杂交技术来描绘人类核型与两种狐猴物种（黑美狐猴指名亚种和马约特美狐猴）核型之间的同源性。通过双变量荧光激活流式细胞分选（FACS）以及随后的简并寡核苷酸引物PCR（DOP-PCR），建立了人类和狐猴染色体特异性探针。将人类探针与狐猴染色体进行相互杂交，反之亦然，这使得我们能够详细分析这些物种进化过程中发生的染色体间重排。结果表明，在超过4500万年的狐猴和人类进化过程中，这两个物种的基因组仅发生了少数易位。发现与人类染色体3、9、11、13、14、17、18、20、21、X和Y同源的染色体在这两种狐猴物种中是保守的。以非灵长类哺乳动物作为灵长类的外类群，确定了各种灵长类染色体的祖先状态，并将其与衍生形式区分开来。狐猴染色体涂染探针也用于两种狐猴物种之间的跨物种杂交。结果支持了基于染色体带型做出的早期假设，即这两个物种的核型完全是通过罗伯逊易位进化而来的。所有源自马约特美狐猴染色体、与黑美狐猴指名亚种重排中涉及的同源物特异性相关的探针，都专门涂染了整个染色体臂。结果进一步表明，马约特美狐猴的核型很可能比黑美狐猴指名亚种的核型更具祖先特征。源自原猴亚目的探针将有助于比较其他低等灵长类动物的核型，这将增进我们对早期灵长类基因组进化的理解。
