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Recombinant inbred strains of mice were used to localize the genes coding for the class alpha glutathione S-transferase 2 (Gst-2). The genes showed three distinct strain distribution patterns, indicating that they occur in at least three clusters separable by recombination. All three clusters are located in the vicinity of the d locus on mouse chromosome 9, but two of them are closer to d than the third. Linked to Gst-2 on mouse chromosome 9 are two enzyme-encoding loci, Pgm-3 and Mod-1. The human counterparts of Gst-2, Pgm-3, and Mod-1 map to 6p12, 6q12, and 6q12, respectively. Thus, the pericentric region of human chromosome 6 has its homolog in the segment spanning Gst-2, Pgm-3, and Mod-1 on mouse chromosome 9. The fact that the syntenic group extends across the centromere of human chromosome 6 can best be explained by a pericentric inversion postulated to have taken place in the primate lineage leading to Catarhini. 相似文献
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Abstract. 1. Developmental costs of rapid growth in terms of increased fluctuating asymmetry are expected to contribute to the widespread occurrence of growth rates below the physiological maximum, but have rarely been demonstrated. Here, these costs are studied for the first time in an invertebrate, the damselfly Lestes viridis , using a rearing experiment where early- and late-hatched larvae of both sexes were reared at decreasing or permanent water levels.
2. Late-hatched animals were more asymmetrical than early-hatched animals except for males in the drying treatment. Also, females were more asymmetrical than males except in early-hatched animals in the drying treatment.
3. The data presented suggest that in females but not in males treatment groups with higher growth rates have more asymmetrical wings. However, at the individual level no relationship between growth rate and asymmetry was present.
4. Possible reasons why the suggested trade-off between growth and developmental instability was not present at the individual level, and at the group level only in females, are discussed. 相似文献
2. Late-hatched animals were more asymmetrical than early-hatched animals except for males in the drying treatment. Also, females were more asymmetrical than males except in early-hatched animals in the drying treatment.
3. The data presented suggest that in females but not in males treatment groups with higher growth rates have more asymmetrical wings. However, at the individual level no relationship between growth rate and asymmetry was present.
4. Possible reasons why the suggested trade-off between growth and developmental instability was not present at the individual level, and at the group level only in females, are discussed. 相似文献
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