Scientists have created the first man- made chromosome for a complex-celled organism -- a feat hailed as a big step towards acquiring the controversial ability to redesign plants or animals. A synthetic chromosome was inserted into a brewer's yeast cell, which functioned as normal -- the key test of success, the international team reported in the journal Science.
"Our research moves the needle in synthetic biology from theory to reality," said Jef Boeke, director of the New York University's Institute for Systems Genetics, who was a member of the research team. Yeast is a closely-studied representative of the group of eukaryotes, organisms with complex cells that contain a nucleus and other structures enclosed within membranes.
All plants and animals, including humans, have eukaryotic cells. Chromosomes have previously been synthesised for bacteria, which are simpler, prokaryotic organisms. Yeast is used to make beer, biofuel and medicines, and researchers believe it can be made to work more efficiently with genetic modifications.
Important points - chromosome
ü In each human cell, except the egg and sperm cells, there are 46 paired chromosomes of varying size
ü One chromosome of each pair is inherited from each parent
ü The autosomes are chromosomes numbered 1-22 (largest to smallest)
ü The two sex chromosomes are called X and Y
ü Egg cells contain 23 chromosomes, made up of 22 autosomes and an X
ü Sperm cells contain 23 chromosomes, made up of 22 autosomes and an X or a Y
ü When the egg and sperm join at conception, the baby will have 46 chromosomes in its cells, just like the parents
What are chromosomes?
Chromosomes are tiny structures inside cells made from DNA, RNA, and protein.
Inside the Cell
Chromosomes are found in the nucleus of every cell. Different forms of life have a different number of chromosomes in each cell. Humans have 23 pairs of chromosomes for a total of 46 chromosomes in each cell.
Different chromosomes carry different types of information. For example, one chromosome may contain information on eye color and height while another chromosome may determine blood type.
Within each chromosome are specific sections of DNA called genes. Each gene contains the code or recipe to make a specific protein. These proteins determine how we grow and what traits we inherit from our parents. The gene is sometimes called a unit of heredity.
Chromosomes in Different Animals
Different organisms have different numbers of chromosomes: a horse has 64, a rabbit 44, and a fruit fly has 8.