Lowe X R, de Stoppelaar J M, Bishop J, Cassel M, Hoebee B, Moore D, Wyrobek A J
Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, CA 94550, USA.
Environ Mol Mutagen. 1998;31(2):125-32.
A multicolor fluorescence in situ hybridization (FISH) method was developed to detect aneuploidy and diploidy in epididymal sperm of rats using DNA probes specific for chromosomes 4 and Y. Fourteen healthy young-adult rats from three strains were evaluated: inbred Fisher 344/N/ehs, outbred Sprague-Dawley, and outbred WU Wistar/CPB. The hybridization efficiency of the FISH procedure was > 99.9%, the sex-ratio in sperm was approximately 1 as expected, and there was no significant variation among two independent scorers. No significant variations were detected within or among strains in the frequencies of sperm disomy for chromosome 4 (1-6.5 per 10,000 cell per animal) or the Y chromosome (0-2.5 per 10,000 cells per animal). There was a trend toward increased variation among Wistar rats. The frequencies of sperm-carrying hyper- and hypohaploidy for chromosome 4 were similar, suggesting a symmetrical mechanism of chromosome gain and loss during meiosis. The frequencies of Y-Y-4-4 sperm, which represent genomic meiosis II errors, did not differ significantly across strains (0.1-0.7 per 10,000 cells per strain). This FISH method for detecting aneuploidy in rat epididymal sperm provides a promising interspecies biomarker of male germ cell aneuploidy and introduces the rat as an animal model for investigating the heritable risk to offspring associated with paternal genotype, physiology, and exposure to environmental mutagens. There appear to be no significant differences among young healthy rats, mice, and men in the baseline frequencies of sperm with Y chromosomal disomy, the only chromosome for which data currently exists for all three species.
开发了一种多色荧光原位杂交（FISH）方法，使用针对4号染色体和Y染色体的DNA探针来检测大鼠附睾精子中的非整倍体和二倍体。对来自三个品系的14只健康成年大鼠进行了评估：近交系Fisher 344/N/ehs、远交系Sprague-Dawley和远交系WU Wistar/CPB。FISH程序的杂交效率>99.9%，精子中的性别比与预期接近，约为1，并且两个独立评分者之间没有显著差异。在4号染色体（每只动物每10000个细胞中1-6.5个）或Y染色体（每只动物每10000个细胞中0-2.5个）的精子二体频率方面，品系内或品系间均未检测到显著差异。Wistar大鼠之间的差异有增加的趋势。4号染色体携带超单倍体和亚单倍体精子的频率相似，表明减数分裂过程中染色体增减的机制是对称的。代表基因组减数分裂II错误的Y-Y-4-4精子的频率在各品系间没有显著差异（每个品系每10000个细胞中0.1-0.7个）。这种用于检测大鼠附睾精子非整倍体的FISH方法为雄性生殖细胞非整倍体提供了一种有前景的种间生物标志物，并引入大鼠作为动物模型，用于研究与父本基因型、生理状况以及暴露于环境诱变剂相关的后代遗传风险。在年轻健康大鼠、小鼠和男性中，Y染色体二体精子的基线频率似乎没有显著差异，Y染色体是目前这三个物种都有数据的唯一染色体。
