The research team led by American researchers released the first complete and seamless human genome sequence on March 31. Six papers related to this major achievement were published in the American journal Science on the same day. The international research team "telomere to telomere alliance", led by researchers from the National Human Genome Institute, the University of California Santa Cruz and the University of Washington, completed the study. The US National Human Genome Institute said in a bulletin that the human genome contains about 3 billion DNA (deoxyribonucleic acid) base pairs. Completing the complete and gapless sequencing of these base pairs is very important for understanding the full spectrum of human genome variation and mastering the impact of genes on some diseases. The communique said that the analysis of the complete human genome sequence will significantly increase scientists' understanding of human chromosomes, thus opening up new research directions. This helps to solve the basic biological problems such as how chromosomes separate and divide. The research team also found more than 2 million additional gene variants using the complete human genome sequence. These studies provided more accurate gene variation information for 622 medical-related genes. Eric green, director of the National Human Genome Institute, said that the completion of complete human genome sequencing is an important scientific achievement and provides the first comprehensive perspective for understanding human DNA. These basic information will enhance the understanding of all subtle functional differences of the human genome and promote the genetic research of human diseases. The significance of the human genome sequencing project is considered to be equivalent to the Apollo moon landing program. Human genome contains human genetic information. Deciphering it can bring revolutionary progress to disease diagnosis, new drug research and development, new therapy exploration and so on. In 2001, the international "human genome project", which was jointly participated by scientists from six countries including China, published a draft and preliminary analysis of the human genome in the British journal Nature. Due to the limitations of sequencing technology at that time, there were many gaps in the draft human genome. (Xinhua News Agency)