The ability to reproduce is the key trait that distinguishes living organisms from inorganic matter, and the strategies used to achieve successful reproduction are almost as diverse as the organisms themselves. In animals, the most widespread form of reproduction involves separate male and female sexes: Each sex produces haploid gametes via meiosis, and two gametes fuse to form a new diploid organism. In some cases, both parents contribute equally to the nuclear and cytoplasmic genomes of their offspring. However, such fully symmetric reproduction of both parents represents the extreme end of a continuum toward complete asymmetry, where offspring inherit their nuclear and cytoplasmic genomes from only one of the two parents. Asymmetries also occur with respect to the fate of maternally and paternally inherited genomes and which sex is affected by non-Mendelian inheritance. In this review, we describe the diversity of animal reproductive systems along different axes with a symmetry–asymmetry continuum and suggest evolutionary routes that may have led to increased levels of asymmetry.

中文翻译：

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不对称遗传：非孟德尔生殖策略的多样性和进化

繁殖能力是区分生物体和无机物的关键特征，用于实现成功繁殖的策略几乎与生物体本身一样多种多样。在动物中，最普遍的繁殖形式涉及不同的雄性和雌性：每种性别通过减数分裂产生单倍体配子，两个配子融合形成新的二倍体生物。在某些情况下，父母双方对其后代的核和细胞质基因组的贡献相同。然而，父母双方这种完全对称的繁殖代表了走向完全不对称的连续体的极端，即后代仅从父母之一继承其核和细胞质基因组。母系和父系遗传基因组的命运以及性别受到非孟德尔遗传的影响也存在不对称性。在这篇综述中，我们描述了动物生殖系统沿着不同轴的多样性，具有对称-不对称连续体，并提出了可能导致不对称程度增加的进化路线。