Szamalek Justyna M, Goidts Violaine, Cooper David N, Hameister Horst, Kehrer-Sawatzki Hildegard
Department of Human Genetics, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
Hum Genet. 2006 Aug;120(1):126-38. doi: 10.1007/s00439-006-0209-y. Epub 2006 Jun 15.
The human and chimpanzee genomes are distinguishable in terms of ten gross karyotypic differences including nine pericentric inversions and a chromosomal fusion. Seven of these large pericentric inversions are chimpanzee-specific whereas two of them, involving human chromosomes 1 and 18, were fixed in the human lineage after the divergence of humans and chimpanzees. We have performed detailed molecular and computational characterization of the breakpoint regions of the human-specific inversion of chromosome 1. FISH analysis and sequence comparisons together revealed that the pericentromeric region of HSA 1 contains numerous segmental duplications that display a high degree of sequence similarity between both chromosomal arms. Detailed analysis of these regions has allowed us to refine the p-arm breakpoint region to a 154.2 kb interval at 1p11.2 and the q-arm breakpoint region to a 562.6 kb interval at 1q21.1. Both breakpoint regions contain human-specific segmental duplications arranged in inverted orientation. We therefore propose that the pericentric inversion of HSA 1 was mediated by intra-chromosomal non-homologous recombination between these highly homologous segmental duplications that had themselves arisen only recently in the human lineage by duplicative transposition.
人类和黑猩猩的基因组在十个明显的核型差异方面有所不同，包括九个臂间倒位和一次染色体融合。其中七个大的臂间倒位是黑猩猩特有的，而其中两个涉及人类1号和18号染色体的倒位，在人类和黑猩猩分化之后在人类谱系中固定下来。我们对人类1号染色体特异性倒位的断点区域进行了详细的分子和计算表征。荧光原位杂交（FISH）分析和序列比较共同显示，人类1号染色体（HSA 1）的着丝粒周围区域包含大量的片段重复，这些片段重复在两条染色体臂之间显示出高度的序列相似性。对这些区域的详细分析使我们能够将短臂断点区域精确到1p11.2处的154.2 kb区间，长臂断点区域精确到1q21.1处的562.6 kb区间。两个断点区域都包含以反向排列的人类特异性片段重复。因此，我们提出人类1号染色体的臂间倒位是由这些高度同源的片段重复之间的染色体内非同源重组介导的，这些片段重复本身是最近通过复制转座在人类谱系中产生的。
