Skip Navigation Bar
NIH MedlinePlus the Magazine, Trusted Health Information from the National Institutes of Health

Genetics 101

Understanding the Human Genome Project — A Fact Sheet


  • Just a half-century ago, very little was known about the genetic factors that contribute to human disease.
  • In 1953, James Watson and Francis Crick described the double helix structure of deoxyribonucleic acid (DNA), the chemical compound that contains the genetic instructions for building, running, and maintaining living organisms.
  • In 1990, the National Institutes of Health (NIH) and the Department of Energy joined with international partners in a quest to sequence all 3 billion letters, or base pairs, in the human genome, which is the complete set of DNA in the human body. This concerted, public effort was the Human Genome Project.
  • The Human Genome Project's goal was to provide researchers with powerful tools to understand the genetic factors in human disease.
  • All data generated by the Human Genome Project were made freely and rapidly available on the Internet.
  • The Human Genome Project spurred a revolution in biotechnology innovation around the world and played a key role in making the U.S. the global leader in the new biotechnology sector.
  • In April 2003, researchers successfully completed the Human Genome Project, under budget and more than two years ahead of schedule.


  • The Human Genome Project has already fueled the discovery of more than 1,800 disease genes.
  • As a result of the Human Genome Project, today's researchers can find a gene suspected of causing an inherited disease in a matter of days, rather than the years it took before the genome sequence was in hand. There are now more than 2,000 genetic tests for human conditions. These tests enable patients to learn their genetic risks for disease and also help healthcare professionals to diagnose disease.
  • Having the complete sequence of the human genome is similar to having all the pages of a manual needed to make the human body. The challenge now is to determine how to read the contents of these pages and understand how all of these many, complex parts work together in human health and disease.
  • With the drastic decline in the cost of sequencing whole exomes or genomes, groundbreaking comparative genomic studies are now identifiying the causes of rare diseases.
  • Much work still remains to be done. Despite many important genetic discoveries, the genetics of complex diseases such as heart disease are still far from clear.


  • An ambitious new initiative, The Cancer Genome Atlas (, aims to identify all the genetic abnormalities seen in 50 major types of cancer.
  • Based on a deeper understanding of disease at the genomic level, we will see a whole new generation of targeted interventions, many of which will be drugs that are much more effective and cause fewer side effects than those available today.
  • NIH is striving to cut the cost of sequencing an individual's genome to $1,000 or less.
  • Individualized analysis based on each person's genome will lead to a powerful form of preventive, personalized and preemptive medicine. By tailoring recommendations to each person's DNA, health care professionals will be able to work with individuals to focus efforts on the specific strategies—from diet to high-tech medical surveillance—that are most likely to maintain health for that particular individual.
  • Professionals will be able to work with individuals to focus efforts on the specific strategies—from diet to high-tech medical surveillance—that are most likely to maintain health for that particular individual.
  • The increasing ability to connect DNA variation with non-medical conditions, such as intelligence and personality traits, will challenge society, making the role of ethical, legal, and social implications research more important than ever.

National Human Genome Research Institute (NHGRI): For the full text of this Human Genome Project Fact Sheet and additional information, contact the Communications and Public Liaison Branch, NHGRI, at (301) 402-0911.

Read More "Genetics 101" Articles

Genetics 101 — The Hereditary Material of Life / GeneEd — A Genetics Educational Resource / Using The Genetics Home Reference Website / Understanding the Human Genome Project — A Fact Sheet

Summer 2013 Issue: Volume 8 Number 2 Page 15