African great apes have large constitutive heterochromatin (C-band) blocks in subtelomeric regions of the majority of their chromosomes, but humans lack these. Additionally, the chimpanzee meiotic cell division process demonstrates unique partial terminal associations in the first meiotic prophase (pachytene). These are likely formed as a result of interaction among subtelomeric C-band blocks. We thus conducted an extensive study to define the features in the subtelomeric heterochromatic regions of chimpanzee chromosomes undergoing mitotic metaphase and meiotic cell division. Molecular cytogenetic analyses with probes of both subterminal satellite DNA (a main component of C-band) and rDNA demonstrated principles of interaction among DNA arrays. The results suggest that homologous and ectopic recombination through persistent subtelomeric associations (post-bouquet association observed in 32% of spermatocytes in the pachytene stage) appears to create variability in heterochromatin patterns and simultaneously restrain subtelomeric genome polymorphisms. That is, the meeting of non-homologous chromosome termini sets the stage for ectopic pairing which, in turn, is the mechanism for generating variability and genomic dispersion of subtelomeric C-band blocks through a system of concerted evolution. Comparison between the present study and previous reports indicated that the chromosomal distribution rate of sutelomeric regions seems to have antagonistic correlation with arm numbers holding subterminal satellite blocks in humans, chimpanzees, and gorillas. That is, the increase of subterminal satellite blocks probably reduces genomic diversity in the subtelomeric regions. The acquisition vs. loss of the subtelomeric C-band blocks is postulated as the underlying engine of this chromosomal differentiation yielded by meiotic chromosomal interaction.

中文翻译：

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从黑猩猩染色体末端的减数分裂构型推断，亚末端卫星块的结构变异及其来源机制。

非洲大猿在其大多数染色体的亚端粒区域具有大的本构异染色质（C带）区，但人类却没有。此外，黑猩猩减数分裂细胞分裂过程显示出在第一个减数分裂前期（粗线期）中独特的部分末端缔合。这些可能是由于亚端粒C波段模块之间相互作用的结果而形成的。因此，我们进行了广泛的研究，以定义经历有丝分裂中期和减数分裂细胞分裂的黑猩猩染色体的亚端粒异色区域中的特征。用亚末端卫星DNA（C波段的主要成分）和rDNA的探针进行分子细胞遗传学分析，证明了DNA阵列之间相互作用的原理。结果表明，通过持久的亚端粒缔合（在32％的精子细胞在粗线期观察到花束结合），同源和异位重组似乎在异染色质模式中产生了变异性，同时抑制了亚端粒基因组多态性。也就是说，非同源染色体末端的相遇为异位配对奠定了基础，而异位配对又是通过协调进化系统产生亚端粒C波段区的变异性和基因组分散的机制。本研究与先前报道之间的比较表明，在人类，黑猩猩和大猩猩中，sutelomeric区的染色体分布速率似乎与持有亚末端卫星区的臂数具有拮抗性。那是，子末端卫星块的增加可能会降低亚端粒区域的基因组多样性。假定亚变体C带区的获取与丢失是减数分裂染色体相互作用产生的这种染色体分化的基础引擎。