Homology of some RNAs with template DNA requires systematic exchanges between nucleotides. Such exchanges produce ‘swinger’ RNA along 23 bijective transformations (nine symmetric, X ↔ Y; and 14 asymmetric, X → Y → Z → X, for example A ↔ C and A → C → G → A, respectively). Here, analyses compare amino acids coded by swinger-transformed codons to those coded by untransformed codons, defining coding invariance after transformations. Swinger transformations cluster according to coding invariance in four groups characterized by transformations into cytosine (C = C, T → C, A → C, and G → C). C’s central mutational coding role shows that swinger transformations constrained genetic code genesis. Coding invariance post-transformations correlate positively/negatively with mitochondrial swinger transcription/lepidosaurian body temperature. Presumably, low/high temperatures stabilize/revert rare swinger polymerization modes, producing long swinger sequences/point mutations, respectively. Coding invariance after swinger transformations might compensate effects of swinger polymerizations in species with low body temperatures. Hypothetically, swinger transcription increased coding potential of RNA self-replicating protolife systems under heating/cooling cycles.

中文翻译：

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双射密码子转换显示了以胞嘧啶的编码特性为中心的遗传密码对称性。

一些具有模板DNA的RNA的同源性要求核苷酸之间进行系统的交换。这样的交换沿着23个双射变换（“ 9个对称，X = Y； 14个不对称，X→Y→Z→X，例如分别为A→C和A→C→G→A”）产生“摇摆” RNA。在这里，分析比较了由swinger转换密码子编码的氨基酸和由未转换密码子编码的氨基酸，定义了转换后的编码不变性。Swinger转换根据编码不变性分为四组，其特征在于转换为胞嘧啶（C = C，T→C，A→C和G→C）。C的中央突变编码作用表明，扫平变换限制了遗传密码的产生。转换后的编码不变性与线粒体扫平仪转录/鳞翅类体温呈正/负相关。想必，低温/高温可稳定/还原稀有的交换剂聚合模式，分别产生较长的交换剂序列/点突变。扫平仪转换后的编码不变性可能会补偿体温较低的物种中的扫平仪聚合效应。假设地，在加热/冷却循环下，swinger转录增加了RNA自复制原型系统的编码潜力。