Genetics (borrowed from Dutch: genetica, adaptation of the English language: genetics, formed from the Greek word γέννω, genno, which means "birth") is a branch of biology that studies heredity and suborganisme in organisms (such as viruses and prions). In short, we can also say that genetics is the study of genes and all its aspects. The term "genetics" was introduced by William Bateson in a personal letter to Adam Chadwick, and he used it at the International Conference on Genetics to-3 in 1906.

The field study started from the subcellular genetic (molecular) to the population. In more detail, trying to explain genetics

    * Material information carriers to be inherited (genetic material),
    * How the information was overexpressed (genetic expression), and
    * How the information is transferred from one individual to another (genetic inheritance).
Table of contents
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    * 1 The beginning and the basic concepts
          o 1.1 The period of pre-Mendelian
          o 1.2 The basic concepts
          o 1.3 The chronology of the development of genetics
    * 2 Branches of Genetics
          2.1 Genetics and forth direction (reverse genetics)
    * 3 References
[Edit] Beginning and basic concepts[Edit] The period of pre-Mendelian
Although people usually define genetics began with the rediscovery of the manuscript articles written Gregor Mendel in 1900, actually genetics as "the science of inheritance" or heredity has been known since prehistoric times, such as the domestication and development of the various races of livestock and crop cultivars. People also are familiar with the effects of crossbreeding and inbreeding, and made a number of procedures and regulations on the matter since before genetic standing as an independent science. The genealogy of the disease in the family, for example, has studied people before that. However, practical knowledge does not provide an explanation of the causes of these symptoms.
Popular theory of inheritance adopted at that time was the theory of mixed inheritance: the average person passing a mixture of qualities that brought tetuanya, especially as it carries sperm from the male. Mendel's research results show that this theory does not apply because the properties were taken in a combination of alleles carried the typical, rather than the mixture evenly. Other relevant opinion is Lamarck's theory: the properties acquired elders in his life bequeathed to his son. This theory is also broken by Mendel's explanation that the properties are not influenced by genes carried by an individual who experiences it inherited trait [1]. Charles Darwin also gave an explanation to the hypothesis of pangenesis and later modified by Francis Galton [2]. In this opinion, the body's cells produce particles called gemmula which will be collected in the reproductive organs before fertilization occurs. Thus, every cell in the body has a contribution to the properties that will be taken zuriat (offspring).

In the pre-Mendelian, people are not familiar with the genes and chromosomes (although DNA has been extracted, but in the 19th century unknown function). At that time people thought the trait is inherited through the sperm (female elders do not contribute anything to the nature of his son).[Edit] The basic concept

Laying a scientific basis through a new systematic experiments carried out in the latter half of the 19th century by Gregor Johann Mendel. He was a monk of Brno (Brünn in German), Austro-Hungarian Empire (now part of the Czech Republic). Mendel generally agreed upon as the 'founder of genetics' after his "über Versuche Pflanzenhybriden" or the Trial of a Plant Crosses (print published in 1866) independently rediscovered by Hugo de Vries, Carl Correns, and Erich von Tschermak in 1900. In his work, Mendel first discovered that the inheritance of traits in plants (he uses the seven traits in pea plants, Pisum sativum) following a number of simple mathematical ratio. More important, he can explain how the ratio-ratio of this case, through what is known as the 'Laws of Inheritance Mendel'.
From this work, people began to recognize the concept of the gene (Mendel called "factors"). Genes are hereditary. Allele is an alternative expression of genes in association with a trait. Each individual disomik always have a pair of alleles, which corresponds to a typical trait, each derived from tetuanya. Status of the pair of alleles is called genotype. If an individual has the same pair of alleles, genotypes of individuals were homozygous genotype, if the partner is different, the individual genotypes in heterozygous state. Genotypes associated with the observed properties. Properties associated with a genotype is called phenotype.[Edit] Chronology of developmental genetics
After the discovery of re-work of Mendel, genetics is growing very rapidly. Developmental genetics is often a classic example of the use of scientific method in science or science.
Here are the phases of the development of genetics:

    * 1859 Charles Darwin published The Origin of Species, as the basis of genetic variation.;
    * 1865 Gregor Mendel's Experiments submit manuscripts on Plant Crosses;
    * 1878 E. Strassburger provide an explanation of double fertilization;
    * 1900 The rediscovery of Mendel's work separately by Hugo de Vries (Belgium), Carl Correns (Germany), and Erich von Tschermak (Austro-Hungary) ==> the beginning of classical genetics;
    * 1903 chromosomes known to be a unit of genetic inheritance;
    * 1905 British biologist William Bateson Experts mengkoinekan the term 'genetics';
    * 1908 and 1909 Laying the basis of population genetics theory by Weinberg (German physician) and separately by James W. Hardy (English mathematician) ==> the beginning of population genetics;
    * 1910 Thomas Hunt Morgan showed that genes located on chromosomes, using the fruit fly (Drosophila melanogaster) ==> initial cytogenetic;
    * 1913 Alfred Sturtevant makes the first genetic map of a chromosome;
    * 1918 Ronald Fisher (biostatistika experts from the UK) publishes On the correlation the between relatives on the supposition of Mendelian inheritance (freely means "Linkage antarkerabat based on Mendelian inheritance"), which ended the feud between the theory of biometry (Pearson et al.) And the theory of Mendel at once initiate the synthesis of both ==> initial quantitative genetics;
    * 1927 Physical changes in genes are called mutations;
    * 1928 Frederick Griffith discovers a hereditary molecule that is transmissible between bacteria (conjugation);
    * 1931 Crossing over leads to recombination;
    * 1941 Edward Lawrie Tatum and George Wells Beadle show that genes encode proteins, ==> initial central dogma of genetics;
    * 1944 Oswald Theodore Avery, Colin McLeod and Maclyn McCarty isolate DNA as genetic material (they call it the principle of transformation);
    * 1950 Erwin Chargaff shows the existence of general rules that apply to the four nucleotides in nucleic acids, for example, tend to be as much adenine with thymine;
    * 1950 Barbara McClintock discovers transposons in maize;
    * 1952 Hershey and Chase experiment proves the genetic information of phages (and all other organisms) is DNA;
    * 1953 The puzzle of DNA structure is answered by James D. Watson and Francis Crick of the double stranded (double helix), based on images of X-ray diffraction of DNA from Rosalind Franklin ==> initial molecular genetics;
    * 1956 Jo Hin Tjio and Albert Levan established that the human chromosome number 46;
    * 1958 Meselson-Stahl experiment showed that the DNA is duplicated (replicated) is semiconservatively
    * 1961 The genetic code is arranged in triplets;
    * 1964 Howard Temin showed using RNA viruses that Watson's central dogma is not always true;
    * 1970 restriction enzymes found in bacteria Haemophilus influenzae, makes it possible to do the cutting and splicing DNA by the researcher (see also RFLP) ==> the beginning of modern biotechnology;
    * 1977 DNA is sequenced first time by Fred Sanger, Walter Gilbert and Allan Maxam working independently. Tim Sanger successfully sequenced the entire genome of Bacteriophage Φ-X174;, a virus ==> beginning of genomics;
    * 1983 Multiplication (amplification) of DNA can be done easily after Kary Banks Mullis discovered polymerase chain reaction (PCR);
    * 1985 Alec Jeffreys invented genetic fingerprinting.
    * 1989 was first sequenced human gene encoding the CFTR protein cause cystic fibrosis;
    * 1989 Laying a strong foundation for the statistical analysis of quantitative trait loci (QTL analysis);
    * 1995 Sequencing the genome of Haemophilus influenzae, which became the first genome sequencing of a free living organism;
    * 1996 first eukaryote genome sequence: the yeast Saccharomyces cerevisiae;
    * 1998 The results of the first sequencing of multicellular eukaryotes, the nematode Caenorhabditis elegans, was announced;
    * 2001 initial draft human genome sequence was released to coincide with the start of the Human Genome Project;
    * 2003 The Human Genome Project (Human Genome Project) completed 99% work on the date (14 April) with an accuracy of 99.99% [1]

[Edit] Branches of Genetics
Genetics develops either as a pure science and applied science. Branches of science are formed mainly as a result of the deepening of a particular aspect of the object of study.
Branches of pure genetics:

    * Molecular genetics
    * Cell genetics (cytogenetics)
    * Population genetics
    Quantitative genetics *
    Developmental genetics *
The branches of applied genetics:

    * Medical genetics
    * Science of breeding
    * Genetically modified or engineered genes
Biotechnology is an applied science that is not directly a branch of genetics but is closely related to developments in the field of genetics.[Edit] Genetics and forth direction (reverse genetics)
Classical genetic studies of symptom phenotype begins (which is invisible to the human observation) and then looked for an explanation genotipiknya up to the level of genes. Development of techniques in molecular genetics quickly and efficiently bring new philosophy in genetics methodology, by reversing the direction of the study. Because many genes already identified the sequence, the insert or change a gene in a chromosome and then look at the implications of phenotypic happen. Analysis techniques that use this philosophy are grouped in the study of genetics and forth direction or reverse genetics, while the techniques of classical genetics studies genetics called direction-forward or forward genetics.