Last update:

   10-Sep-2004
 

Arch Hellen Med, 18(5), September-October 2001, 475-484

REVIEW

Τhe human genome project

E. KANAVAKIS, A. XAIDARA
Medical Genetics, University of Athens, "Agia Sophia" Children's Hospital, Athens, Greece

Mapping the human genome is considered to be the most important development in biology with great implications for medical science. The goal of the Human Genome Project is to sequence the entire human genome, which contains the whole genetic information. The human genome consists of 3 billion base pairs of DNA which are distributed among 24 distinct chromosomes, 22 autosomes and 2 sex chromosomes. Within this vast array of nucleotides is encoded an estimated 50,000 to 100,000 genes and the necessary elements controlling the regulation of their expression. The coding portions of genes represent 2-3% of human DNA. The human genome is characteristic for humans but it is not unique, since the sequence of a normal allele differs from one or more polymorphic alleles by changes affecting the DNA sequence. The Human Genome Project was officially begun in 1990 by the academic research community and was accelerated in 1998 by the efforts of private corporations. The results of both parts were announced in common in June 2000. In February 2001, each sector reported update data with its own separate publication. Applications of genetic knowledge have a broad impact on both diagnosis and treatment. Genetic diagnosis is used for prevention of genetic diseases by means of either prenatal of preclinical presymptomatic diagnosis. Approximately 1,000 genetic diseases have already been studied and the gene responsible for them have been cloned. Genetic tests are now available for disorders which have lower penetrance or later onset and for which there are available limited interventions and inadequate or no treatment. Genetic tests can identify those who are affected with genetic diseases but also those who are healthy carriers of disorders or have the genetic predisposion to develop a disease if exposed to a specific environmental factor. Knowing the genetic information can prevent or delay the development of the disease or result in the better course and prognosis of the disease. As far as therapeutic intervention is concerned, medicines tailored in specific genes and the ongoing research in gene or nucleic acids therapy will lead to diminished drug side effects and permit better or permanent disease control. Comparative genomics assists in better understanding of the gene environment and helps in identifying genes responsible for multifactorial diseases. It is obvious that the application of the knowledge obtained by the Human Genome Project raises ethical, legal and social issues. The goal of the study of the potential benefits and adverse consequences is to create legislation and public policies which will set the framework for assertion of autonomy, consent, privacy and ownership of the genetic information, protection from stigmatization, discrimination or modification of human relationships, and justification of the human interests and human rights.

Key words: DNA sequence, Genes, Genetics, Human genome, Polymorphisms.


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