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Nuclear transfer research encompasses some of the most compelling biological and ethical puzzles of our time. In an online publishing experiment, we asked you, The Scientist readers, to help us create the article. Here's how you would solve the mysteries of the egg, fertilization, and cloning.

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The thunder of a late spring rain rumbles through Philadelphia. Inside a Temple University lab, an ovulated mouse egg rests in metaphase II. Devoid of a nuclear envelope, its chromosomes lie naked, held near the edge of the cell, suspended mid division by a spindle, and just barely visible as a bright hump in the near perfect sphere.

If a sperm were to enter this cell, it would set off a remarkable chain of events: The completion of meiosis and extrusion of a second polar body containing 20 maternal chromosomes; the stripping of protamines from the sperm's DNA and replacement with histones; the unification and reprogramming of the two haploid genomes; and eventually a rapid succession of divisions that transform the cell from egg to embryo with some potential to become a full...