Genes Chromosomes GENOME The nucleus of a human

Genes & Chromosomes

GENOME The nucleus of a human cell contains between 30 000 and 40 000 genes. This complete set of genes is called the GENOME.

Structure of the Genome �Tightly coiled threads of deoxyribonucleic acid (DNA) and associated protein molecules �Organized into structures called chromosomes

What are CHROMOSOMES? �A packet of coiled up DNA �Humans have 23 pairs of chromosomes �They are in the nucleus of cells

What are CHROMOSOMES? �Chromosomes contain a single, long piece of DNA �A chromosome is about 0. 004 mm long �The DNA is about 4 cm long �This is about 10 000 times longer than the chromosome So it has to twist and coil to fit inside

What are CHROMOSOMES? �There are 23 pairs of chromosomes in the nucleus of any one of your cells �Each chromosome has a double strand of DNA (deoxyribonucleic acid) which carries the code for a couple of thousand genes

What is a GENE?

What is a GENE? �A code made up of pairs of bases carried on the DNA molecule. �Each DNA molecule contains many genes �The basic physical and functional units of heredity

What is a GENE? �A specific sequence of bases Sequences carry the information needed for constructing proteins �The human genome is estimated to be made of more than 30, 000 genes.

What is a GENE? �Each chromosome carries a couple of thousand genes �Many of these are common to all human beings. �So, 99. 5% of your DNA is identical to everyone else's

What is a GENE? �The remaining 0. 5% influences the differences between us height, hair color and susceptibility to a particular disease �Environmental factors, such as lifestyle (for example, smoking and nutrition) also influence the way we look and our susceptibility to disease

SNP’s �Single nucleotide polymorhism

Genomes of other organisms in relation to human beings

Pair of Chromosomes �Chimpanzees - 24 pairs of Chromosomes �Rhesus Monkey – 21 pairs �Cow – 30 pairs �Chicken – 39 pairs �Fruit Fly – 4 pairs �Banana – 11 pairs �Chimpanzees share 98. 5 % of its DNA to humans while Rhesus Monkeys share 93%.

The Human Genome Project: The Holy Grail of Biology

Institutions that conducted the research National Human Genome Research Institute Department of Energy (U. S. )

US President George W. Bush said: "The genetic map provides us the fundamental platform for understanding ourselves from which revolutionary progress will be made in biomedical sciences and in the health and welfare of humankind"

Sir James D. Watson said: �"Never would have dreamed in 1953 that my scientific life would encompass the path from DNA's double helix to the 3 billion steps of the human genome. But when the opportunity arose to sequence the Human Genome, I knew it was something that could be done - and that must be done”

What is the Human Genome? �The entire genetic makeup of the human cell nucleus.

Goals of the Human Genome Project �Identify all of the genes in human DNA. �Determine the sequence of the 3 billion chemical nucleotide bases that make up human DNA. �Store this information in data bases. �Develop faster, more efficient sequencing technologies. �Develop tools for data analysis. �Address the ethical, legal, and social issues (ELSI) that ay arise form the project.

Published �The International Human Genome Sequencing Consortium published their results in Nature, 409 (6822): 860 -921, 2001. “Initial Sequencing and Analysis of the Human Genome” �Celera Genomics published their results in Science, Vol 291(5507): 1304 -1351, 2001. “The Sequence of the Human Genome”

April 14, 2003 �The International Human Genome Sequencing Consortium, led in the United States by the National Human Genome Research Institute (NHGRI) and the Department of Energy (DOE), announced in Bethesda, US on April 14, 2003, the successful completion of Human Genome Project more than two years ahead of schedule.