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The first genetics terms were formulated due to the agricultural and therapeutic activity
of people. The historical documents prove that pedigrees had been used in breed even 6000
years ago. Observations concerning many pathological traits connected with heredity are
reflected in religious documents especially in Talmud (IV - V century before Christ).
The factors that stimulated people to researches about heredity were: a development
of breeding in the second half of XIX century and Darwin's works about the
origin of species. A lot of discoveries, which played significant part in the development
of genetics, were made. These contained the description of special cell structures - chromosomes,
stating their constant amount and individual morphologic
features in cells of specific species and discovering that during the creation of gender cells
the amount of chromosomes reduces two times.In 1865 G. Mendel published the work in which he formulated the basic genetic laws. The official date of birth of genetics is established for 1900 when H. de Vries, K. Correns i K. Tschermak's data was published. They were in fact bringing back to life the forgotten Mendel's works about the inheritance of traits. The researchers expressed the results of their and Mendel's work in laws, known today as Mendel's laws. 
The first decades of XX century became very favourable to the development of the basic
assumptions of genetics. The theories formulated in those times were: the thery of
mutations by H. de Vries, theory of heredity by T. G. Morgan. It was stated
by J. S. Philippow and J. Moeller that the x-ray radiation causes genetic changes.
N. K. Kolcow formulated thesis that the chemical basis of a gene are biological macro
- cells. A. Garrod pointed the connection between genes and enzymes. G. H. Hardy,
W. Veinberg and S. S. Czietwierikow started working out the bases of population genetics.
It was noticed that some diseases have genetic origin.The most significant moment for the development of modern genetics was discovering DNA "the genetic substance", decoding the genetic code and describing the mechanism of biosyntesis of proteins. |
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1866 Theory of heredity Austrian monk Gregory Mendel discovers inheritance laws, crossing and observing pea plants in his garden next to the maonastery. 1926 Changes in genes American biologist Herman Muller states that x - ray radiation causes changes in genes of fly, so called mutations. 1944 The carrier of information Oswald Avery and Maclyn McCarty prove that not proteins but DNA is the carrier of information. 1953 The model of DNA structure English biophisicist Francis Crick and American biochemist James Watson work out the model of DNA structure. It's the famous double helix. 1972 The era of biotechnology American biochemist Paul Berg joins DNA of virus with the DNA of bactery. It's a beginning of the era of biotechnology. 1973 Moving genes American biochemists Stanley Cohen and Herbert Boyer move genes from one organism to another - part of DNA of ...... to DNA of bactery. 1982 Insulin "Humulin" that is human insulin appears on a market. It's produced by geneticly modified bacteries which have a human gene inserted into their body. The gene directs producing insulin identical to the one produced by a human pancreas. 1985 Genetic fingerprints Alec Jeffreys from the University of Leicester works out technique of "genetic fingerprints". It allows to identify a man on the basis of analisis of their DNA. A few years later these techniques will be used in criminalogy - to identification of criminals on the basis of remains of their skin or hair. 1988 Aim: describing human DNA Human Genome Poject starts its work. Its aim is to describe full human DNA. It's a .. - human DNA consists of over 3 miliards of pairs of nucleotides. 1993 Cloning an embryo The scientists from The George Washington University clone human embryos and breed them several days. It arouses plenty of protests. 1995 Transplantations of organs American biotechnologists inform about success in transplanting a heart of a transgenic pig to a monkey. Thanks to the modifications of the pig DNA its organs weren't rejected by immunology system of a monkey. It gives scientists hope that someday animal organs will be transplanted to peaple. 1997 A cloned sheep A group of scientists from Roslin Institute in Scotland informs about birth of Dolly - the sheep cloned from an adult animan cell. 1998 Generation of clones The scientists from the Unversity of Havai manage to get 3 generations of mouse clones. |
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