中文摘要：

为了进一步研究P53抑癌基因的性质,采用信号处理和分析的方法,在Voss数值映射下,利用离散傅里叶变换,结合出现最大功率谱位置的频率与1/3的差值（d）及信噪比（R）两个指标,来讨论P53家族基因的碱基三周期性。选取人类P53家族（P53、P63和P73）DNA序列及家鼠P53家族DNA序列的外显子,讨论了其三周期性与外显子长度、碱基成分及碱基分布的关系,在三周期性的前提下分析了P53基因密码子的偏好性。结果表明：P53家族基因的短外显子（N〈100）碱基三周期性不显著,P53家族基因的较长外显子（100≤N〈1000）碱基三周期性较显著;具有三周期性的外显子GC、GC3含量较高,且GC含量和功率谱峰值显著相关,说明三周期性与碱基成分及分布相关;具有三周期性的外显子频谱最大值处为G或C的可能性高,且GC3含量高,R值与最优密码子使用频率正相关,说明功率谱峰值与P53家族基因密码子偏好性具有相关性。该研究结果对P53家族基因的进一步研究具有重要的理论和现实意义。

英文摘要：

The characteristics of P53 cancer suppressor gene was studied by using the method of signal processing and analysis. To be more specifically, under the Voss numerical mapping, two indicators, the difference （d） between the maximum power spectrum and its one-third and the signal-to-noise ratio （R） were combined to discuss the 3-base periodicity of P53 family genes, as well as using the discrete Fourier transform （DFT）. Exons of the DNA sequence of human beings＇ P53 family （P53, P63 and P73） and house mice＇ P53 family were selected to study the relation between the 3-base periodicity and exon＇s length, base composition and base distribution. On the premise of 3-base periodicity theory, the authors analysed P53 genes＇ codon bias. The result illustrated that, the 3-base periodicity of short exons （N〈100） in P53 family genes was not obvious, while the 3-base periodicity of longer exons （100 ≤ N〈1000） in P53 family genes was quite obvious. The exons with the character of 3-base periodicity had a higher content in GC, GC3, and the GC content had obvious relations with spectrum pick value. Also, the 3-base periodicity was related to the composition and distribution of bases. It had the highest possibility that the spectral peak of the 3-base periodicity was G or C, and the content of GC3 was quite high. The R value had a significant relation with frequency of optimal codons（FOP）. There was a positive correlation between the spectrum pick value and P53 family genes＇ codon bias. This research result might lay important theoretical foundation and has prominent practical significance to the further study of P53 family genes.