关于核苷酸序列频谱分析方法的探讨

由A、T、C、G四种字符组成的核苷酸序列本质上是生物分子的一种符号表示。在计算生物学中,常采用离散傅立叶变换进行频谱分析。根据核苷酸序列频率分布的特点和离散傅立叶变换所固有的“栅栏效应”,本文提出采用调频Z变换的分析方法,定义了相应的表达式,同时构造了短时调频Z变换用于识别基因区域中的外显子部分和内含子部分。与已有的基因区域识别算法相比,该方法不需要依赖于训练样本序列。测试结果表明了该方法的有效性。

The Discussion About Frequency-Domain Analysis Way of Nucleotides Sequences

Essentially the nucleotides sequence is a symbolic representation of biomolecular. It can be taken as a kind of discrete signal and do spectrum analysis by discrete Fourier transform. According to its frequency characteristic and the inherent "fence effect" of discrete Fourier transform, we introduc?Chirp Z transform, define its transform formula, and get better spectrum proporties of the sequence comparing with DFT by test data. Based on it we construct short time Chirp Z transform to distinguish between exon regions and intron regions in DNA sequences. This method hardly depeads on the statistical data compared with the existing algorithms. The test results show its validity.