Genomics is the study of the genes which make up the genome. A genome is the totally of all DNA in an individual’s body. While molecular biology concerns itself with the study of single genes or DNA, genomics is concerned with the totality of the genes in the genome and also such intragenomic phenomena as heterosis, pleiotropy and epistasis. In human biology the human genome study which began earlier (McKusick 1980) was almost completely unraveled in the year 2003 after the completion of the so called Human Genome project. The project aims mainly at identifying sequences of all human genes with a view to storing their data to be made available at free gene sequences databases worldwide. With such gene sequences easily available, the genes could be easily manufactured, cloned and passed through rDNA technique, which allows the synthesis of the protein products and the identification of the actions and properties of these proteins or peptides. More importantly, such genes could be constructed for gene therapy, a method of therapeutics of the future.
An extension of the definition of the genome would be the study of interactions between loci and alleles within the genome. The United States Environmental Protection Agency extends its own definition to include the sum total of all genes of an individual and also the DNA which is the genome of the individual, the mRNA, which is the transcriptome and the protein, which is the proteome.
It is said that the genome of all human beings is the same in 99.9% of cases and only differ in the remaining 0.1%. This therefore suggests that race plays very little part in determining the variations in humans at the genetic level. Some would however wish to exploit this 0.1% in what may be called genism, but that is not true science.
The first sequence of gene to be cloned is the bacteriophage MS2 coat protein by Fries in 1972. This was followed by sequence of bacteriophage MS2-RNA. The fist genome to be sequenced was performed by Sanger in Cambridge in 1977 on bacteriophage Φ–X174 which is 5368 bp, The first free living organism to be sequence was Haemophilus influenza in 1995 with 1.5 Mb by Fleischmann et al (1995). By 2007 when the human genome project was completed the complete sequence of 1870 viruses had been known together with 577 bacteria and about 23 eukaryotes, including fungi.
Human Genome Project
The human genome project which was certified to have been completed in the year 2000 was an international scientific effort to map out all the approximately 100,000 genes on the 23 human chromosomes and eventually sequence about 3 billion DNA base pairs which are the constituents of these genes. The project actually started in 1990. It was begun in the US and France and its goal was to understand the genetic basis of human diseases like Alzheimer’s disease and muscular dystrophies and also to understand well the path of human evolution. It was designed to compare the human genome with that of Escherichia coli, a fruit fly and a nematode worm. It took about 15 years to complete and was announced to be complete in 2007. The project of unravelling genomes of other life species still continues.
The human genome project was coordinated by the Department of Energy and also the National Institutes of Health in the USA. It was designed to be a15 year project but it went on for 17 years. It was to transfer technology to the private sector so that it can exploit all the advances in science of this laudable project. It was supposed to have performed the following
· identify all the approximately 30,000 genes in human DNA,
· determine the sequences of the 3 billion chemical base pairs that make up human DNA,
· store this information in databases,
· improve tools for data analysis,
· transfer related technologies to the private sector, and
· address the ethical, legal, and social issues (ELSI) that may arise from the project.
Other species genomes have been mapped and they include