人类基因同义密码子偏好的特征以及与基因GC含量的关系

对人类的728个基因，按其编码区中GC的含量分成四组(从GC＜0.43到GC＞0.58)，分别考察了这四组样本对同义密码子偏好的特征，发现在全部样本中都呈现NTG(N代表四种碱基中的任一种)特受偏爱和NCG尽量避免的特征.基因环境中GC含量与C3/G3含量(密码子第三位C和G的含量)的相关分析，以及四组样本对密码子的偏好都支持以C结尾的密码子在编码中有特殊的优势，这种优势有利于保证翻译的准确性.还考察了各种氨基酸含量随编码区GC含量不同而变化的趋势.

The Features of Synonymous Codon Bias and GC-content Relationship in Human Genes

human genes were divided to four groups according to the GC contents of their coding sequences (from GC<0 43 to GC>0 58). Examination of synonymous codon bias in the 4 groups show that NTG (N represents any base of T, A, C, G) is most favored and NCG is most avoided in all four groups. Statistical correlation analysis of GC content in genetic environment with C3/G3 content (the C or G in the 3rd position of codons) and the codon bias in the four groups suggest that C ending codons are special preferred. This is in favor of accurate translation. Frequency of each amino acid in the four groups was also examined.