History of Genetics Genetics Scope and applications of genetics

History of Genetics
Genetics
Scope and applications of genetics

1. Introduction , Scope and
History of Genetics

2. Introduction
Thestudyoftransferofgenesfromparenttooffsprings.
GENES:Aspecificsequenceofnucleotidesthatencodespecific
proteins.
Etymology:TermwascoinedbyWilliamBatesonin1905andfirstused
byhimin1906inICG(InternationalconferenceonGenetics).
Phrase:ToCodeForisusedthatmeanseverygenecontainspecific
informationaboutproteins.Theconceptonegene,oneproteinisalso
used.

3. AREAS OF GENETIC :
Genetics is divided into 2 main areas :
(A)Classical Genetics: Techniques and methodologies used in genetics are
called classical genetics.
1.Behavioral : The study of influence of varying genetics on animal behavior.
2.Clinical : field of genetics to diagnose and treat and counsel of genetic disorders.
3.Molecular : It focus on structure of gene.
4.Population and Ecological : Subfields of classical genetics.
5.Genomics: Knowledge of large scale of genetic patterns.
6.Genetic Engineering: Manipulation of genes.
(A)Mendelian Genetics: It governs the transfer of heredity characters
from parent to offspring.
This based of Gregor Mendel’s work published in 1865-66. This work was re-discovered by Thomas Hunt Morgan in
1900. He integrated chromosome theory of inheritance i.ecore of classical genetics.

4. Scope/Applications of Genetics
Genetics has scope/role in following fields:
1.Genetics as basis of Biological sciences:
Provide foundation for biological studies. Laws of inheritance help us
to understand the principles of embryology, population, taxonomy,
evolution and ecology.
2.Role of genetics in food production:
Rules of genetics help to introduce new verities of plants and livestock.
3.Disease control:
Gene therapy help to cure many genetics based diseases.
4.Conservation of Wild life:
Conservation of wild life can be achieved in one way by conserving the
germplasm of endangered species.
5.Genetic Engineering/Biotechnology:
Genetic Engineering has many applications including
a.Development of transgenic crops
b.Gene Therapy
c.Improvement in Food production
d.Control of Genetic Diseases

5. e. Gene mapping
6.Behavioral Genetics:
It studies the influence of varying genetics on animal behavior.
7.Clinical Genetics:
There are several genetic disorder exist physicians are trained to diagnose and treat .
8.Molecular Genetics:
It focus on structure and function of gene.
9.Population and Ecological Genetics:
Population and ecological genetics are closely related subfields of genetics. Population
genetics is the study of distribution and change in allele.
10.Genomics:
It allows the study of large scale genetic pattern i.egenomic sequence

6. History of Genetics
1.Mendel’sLaw
•G.MendelwasanAustrianMonk
•StudiedPeaplants(Testedsome28000Plants)b/w1856-1863
•2ObservationsPublishedas“Experimentofhybridization”in1866
2.RediscoveryofMendel’sLaw
•Mendel’sworkprimarilyneglected
•In1900Mendel’sworkwasrediscoveredby3Europeanscientistsi.e
HugodeVaries,CarlCorrensandErichVonTschermak.

7. 3.Role of William Bateson
There were two objection on Mendel’s work
1.Heredity is discontinuous
2.Biologists were not sure about the application of Law on all species
W. Bateson was most active promotor of Mendel’s work in Europe. He
coin many terms related to genetics including genetics, genes and alleles
4. Work of R.A Fisher
R.A Fisher describe that Mendelian factors (genes) were involved for
individual traits
5. Thomas Hunt Morgan (Father of Classical Genetics)
Proposed Chromosomes theory of inheritance

8. Timeline of Notable Discoveries
•1859 Origin of species by C. Darwin
•1865 Experiment on Plant Hybridization by G. Mendel
•1903 Chromosomes Discovered
•1906 Term Genetics Coined by W. Bateson
•1913 Genetic map by Alfred Sturtevant
•1918 R.A Fisher shows correlation traits with factors (genes)
•1927 Physical changes in chromosomes named as “mutation”
•1928 Griffith Experiment on bacteria
•1931 Crossing over was explained by Barbara McClintock

9. •1941 Tatum and Beadle shows that genes are responsible for protein
synthesis
•1944 Avery, McLeod and McCarty isolate DNA
•1950 Chargaff Rule A=T and C=G
Transposons (Jumping Genes) discovered by Barbara
McClintock
•1952 Hershey-Chase experiment prove phages contain DNA as their
genetic information
•1953 DNA is double helical structure proved by two young scientists
Watson and Crick
•1956 Human have 46 Chromosomes proved by Jo HinTjioAlbert
Leaven
•1958 DNA is semiconservative model proved by Measelson-Stahl

10. •1961 Genetic code arranged in triplet (Nirenberg and P.Leder)
•1964 Howard Temimproves Watson central dogma is not always
true.
•1970 Restriction enzyme discovered (Werner Arber)
•1977 DNA sequence was determined by F. Sanger
•1983 Karry B. Mullis discover PCR
•1985 Alec Jeffreys discover DNA finger printing
•1989 Huamangenome sequenced by F. Collins and Lap-Chee Tsui

11. •1995 Genome of H. influenza was sequenced
•1996 yeast genome was sequenced
•1998 Round worm genome was sequenced
•2001 Human Genome was released by Human Genome project and
Celera Genomics simultaneously
•2003 Successful completion of human genome 99% accuracy
•2006 Marcus Pembreyand olovBygrenSex-specific , male line
transgeneratonalresponse. (epigenetics-heritable changes in gene
expression)