What have we learned from the Human Genome Project?

What have we learned from the Human Genome Project?
These major accomplishments in genome sequencing provide a wealth of information that aid in the understanding of basic biological processes. With genome sequence in-hand scientists are now more effectively able to study gene function and explore new areas of research such as how human variation contributes to different diseases worldwide. Scientists today are discovering that the more we learn about the human genome, the more that there is to explore. For instance, as a first step in understanding the genomic code we have learnt that the human genome is made of 3.2 billion nucleotide bases (of which there are four types: A, C, T, G). It is thought that over 30,000 genes are encoded by this sequence. Yet we have also discovered that over 50% of the human genome is repetitive sequence that does not code for any proteins and the function of this large portion of “junk” DNA is still puzzling scientists. Along similar lines, the HGP has shown us that the average length of an expressed gene is 3000 bases long. Genome sequence information has helped scientists more easily identify candidate disease genes, however, we also realize that over 50% of the genes discovered in the human genome are still classified as having unknown function. Human genome sequence information reveals that genome sequences from person to person are almost (99.9%) identical. Interestingly, comparative genomics shows 95% sequence similarity between the human and chimpanzee genomes. Scientists are just beginning to understand how this small amount of variation contributes to differences in disease incidences in different populations. The discovery of about 3 million locations that have single base differences in the human genome (called single nucleotide polymorphisms or SNPs) offers insights into how genomic information could be used to discover information related to the incidence of common human traits, including susceptibility to certain diseases and illnesses.
The HGP has also shown us that the powerful methods of genome sequencing technology raise important ethical and policy issues for individuals and society. Access to genome sequence information, privacy related issues and the appropriate use of this sort of information are all important issues for researchers, governments, and policy makers worldwide. The HGP has great potential to benefit society. An understanding of human variation could be directly translated to human health with the creation of better treatments and personalized medicine. In our complex world, it is also important that human genome information be protected. Scientists, policy makers, educators and ethicists have recognized the need to encourage dialogue with the public about human genome sequence information and potential implications. A number of excellent resources are available online which celebrate human genome based discoveries and provide information about the implications of genomics in today’s society [4].


Figure 2. The Diversity of Genomic Applications to Society. Genomics hold promise for advances in fields ranging from medicine and agriculture, all the way to energy production. This global impact is just beginning to be felt.