Flexi Says: The Human Genome Project is an international project that includes scientists from around the world. It began in 1990, and by 2003, scientists had sequenced all 3 billion base pairs of human DNA. Now they are trying to identify all the genes in the sequence. The Human Genome Project has produced a reference sequence of the human genome. The human genome consists of protein-coding exons, associated introns and regulatory sequences, genes that encode other RNA molecules, and other DNA sequences (sometimes referred to as “junk” DNA), which are regions in which no function as yet been identified. If we are all 99.9% genetically identical, what makes us different? How does that 0.1% make us tall or short, light or dark, develop cancer or not? To understand that 0.1%, we also need to understand the other 99.9%. Understanding the human genome is the goal of the Human Genome Project. However, it is not just determining the 3 billion bases; it is understanding what they mean. How many human genes are there? Do these genes encode transcription factors, transport proteins, growth factors, structural proteins, or oncogenes? Or any of the other various types of proteins? Does a base change in the consensus sequence of a gene cause a genetic disease? What is the phenotype associated with mutations in a specific gene? Because of the HGP, these questions can be addressed. The genes in the genome are in the process of being identified and characterized, as are the proteins associated with those genes. A preliminary estimate of the number of genes in the human genome is around 22,000 to 23,000.
