We consider the problem of designing a set of DNA sequences (DNA codes) for various DNA computing applications, such as DNA based data storage. A chemically active DNA sequence forms unlikely secondary structure by folding back onto itself by hybridization among base pairs. DNA sequences with secondary structures are less active chemically and are needed to unfold before reading. On the other side, during synthesis and sequencing of DNA sequences with homopolymers of large run-length, errors occur frequently. In this letter, we have presented families of DNA codes with several properties such as DNA sequences free from secondary structures of stem length more than two and also free from homopolymers of run-length more than four. All constructed DNA sequences of any DNA codes are sufficiently dissimilar to their reverse-complement DNA sequences. Further, DNA sequences obtained by concatenating all those DNA sequences also avoid secondary structures and homopolymers.

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关于具有多个约束的DNA代码

我们考虑为各种DNA计算应用（例如基于DNA的数据存储）设计一套DNA序列（DNA代码）的问题。具有化学活性的DNA序列通过碱基对之间的杂交而折叠回其自身，从而形成不太可能的二级结构。具有二级结构的DNA序列在化学上活性较低，需要在阅读前展开。另一方面，在具有大游程长度的均聚物的DNA序列的合成和测序期间，经常发生错误。在这封信中，我们介绍了具有若干特性的DNA编码家族，例如不含茎长度大于两个的二级结构且不含游程长度大于四个的均聚物的DNA序列。任何DNA密码的所有构建的DNA序列与其反向互补DNA序列都足够不同。