基因是生物体遗传的基本单位。人类23条染色体上的30亿个碱基对含有约10万个基因,记录了人类生殖细胞的全部生物学信息。人类基因组计划的狭义目标是,从结构上搞清楚30亿个碱基对的 DNA 序列,并且识别出包含在其中的基因,包括搞清其结构及其在人类染色体上的定位。而要真正搞清所有基因的功能,可能是整个21世纪生物科学家的任务 Genes are the basic unit of organism’s inheritance. The 3 billion base pairs on human chromosome 23 contain about 100,000 genes and record all the biological information of human germ cells. The narrow goal of the Human Genome Project is to map out the 3 billion base pair DNA sequences structurally and identify the genes contained in them, including their structure and their location on the human chromosome. And to truly understand the function of all genes may be the task of biologists throughout the 21st century