Scientists and their work related to Genetics

Avery, Macleod and Mc Carty (1944)- proved that DNA is genetic material and gave Biochemical nature of gene (DNA).

Arber, Smith and Nathani- Discovered restriction endonucleases in bacteria which are widely used in genetic engineering.

Altmann- introduced the term "Nucleic acid" in 1989.

A. Folling the Norwegian physician, discovered phenylketonuria in 1934.

Alfred D. Hershey and Martha Chase- proved DNA as genetic material in 1952.

Benzer- Fine structure of gene (cistron, recon and muton)

Briggs and King- Performed transplantation experiments of frog and toad eggs and proved that developmental changes are determined by molecular changes in the nucleus. When the nucleus from young embryonic cell is transplanted into non nucleated egg the tadpole develops.

Bateson- Father of animal genetics, gave the terms allele, F1, F2, homozygous, heterozygous and genetics; applied Mendel's law on animals. Alongwith Punnett, he gave coupling and repulsion theory for genes.

Bridges- Structural and numerical changes in chromosome; discovered nondisjunction of chromosomes and XXY condition in Drosophila genetic balance theory of sex determination.

Blakeslee-Induced polyploidy by using Colchicine Trisomy in Datura.

Beadle and Tatum- One gene one enzyme theory; started biochemical genetics as a new branch; reported Nurtitional mutants (Auxotrophs) in Neurospora crassa (Bread Pink Mould).

Bishop and Varmus- Got Nobel Prize for the discovery of Oncogenes.

Barbara McClintock- Jumping genes (Transpasons) in Maize and got Nobel Prize (1983).

Bateson and Saunders introduced the terms 'homozygote' and 'heterozygote' in 1902.

Crew (1923)- reported a case of complete sex reversal of a fertile fowl (hen).

Camerarius- Sexual reproduction in p

plants.

Correns- Term factor for genes discovered, incomplete dominance in Mirabilis jalapa (40'clock), Cytoplasmic inheritance in 40'clock, term plasmagenes for extranuclear DNA that controls cytoplasmic inheritance; rediscovered Mendel's law and summarised Mendel's assumptions in the form of principles.

Cuenot- Lethal genes in mice.

Cairns- Isolated DNA from E. coli.

Dodge - Father of haploid/Neurospora genetics.

Delbruck, Luria and Hershey- Reproduction and mutations in viruses.

Darwin - Theory of Pangenesis, theory of evolution.

Davenport and Davenport - In 1910, they gave the hypothesis that skin colour is determined by cumulative genes.

Erwin Chargaff - performed chemical studies on the basis of DNA in 1950.

E. Strasburger-In 1875, he observed chromosome during cell division.

Free-Martin- stated that in cattle, when twins are produced, one of them being male and the other female. The female is sterile and male is normal. These are known as Free-Martin.

Frederick Griffith- carried out experiments with Streptococcus pneumonia (bacterium responsible for pneumonia witnessed a miraculous transformation in the bacteria.

F. Baltzer (1935)- studied effect of environment on sex determination in Bonellia vividis.

Fisher- the great German chemist identified two heterocyclic structures- pyrimidines and purines.

Fairchild - Developed first and successful plant hybrid called fairchild mule by crossing carnation and sweet william plants.

Fraenkel Conrat- Confirmed that RNA is genetic material in TMV (plant virus).

Garrod - Father of Human genetics, discovere function errors of metabolism like Aikaptonuria; estabished relationship between and metabolic function.

Gamow- gave idea of triplet nature of genetic code; term genetic code.

Gold Schmidt- Gene is a chemical rather than a physical unit; gynandromorphs in Drosophila.

Hugo de Vries- Mutation theory of evolution, mutations in Oenothera lamarckiana (evening primrose rediscovered Mendel's law.

Harris and Watkins- Protoplast fusion.

Hoagland- Discovered tRNA.

Holley- Clover leaf model of tRNA for yeast alanine. It was having 77 nucleotides.

Henking- X body in sperm of some insects.

Hofmeister- discovered chromosomes in the pollen mother cell of Tradescantia in 1948.

lan Wilmut- of Roslin Institute, Edinburgh, U.K. has produced a clone of adult lamb named "Dolly.

Jeffery - DNA finger printing.

Johannsen- Term gene, genotype, phenotype and pure line.

Jacob and Monod-Operon model for gene regulation concept of mRNA.

Jacob and Wollman- Episome in bacteria.

Kolreuter- Equal contribution of the two sexes in plants. Father of quantitative inheritance he was first to show that traits remain discrete and never blend.

Khorana- in vitro synthesis of gene by linking 77 nucleotide pairs to code for yeast alanine tRNA. Later on he synthesized a functional E. coli tRNAtyrosne glue by linking 207 base pairs; decipher genetic code; discovered DNA T4, ligase enzyme for linking DNA pieces.

Kornberg- in vitro synthesis of DNA but this DNA was ss. DNA polymerase I enzyme.

Lederberg and Hays- Plasmids in bacteria.

Lederberg and Tatum- Sexuality in bacteria.

Lederberg and Zinder- Transduction in bacteria.

Levene - Chemistry of DNA and gave tetranucleotide hypothesis.

Lal Ji Singh- DNA finger printing.

Landsteiner - Blood groups in man but inheritance of blood groups was shown by Bergestein.

Morgan- Father of Experimental Genetics, used Drosophila (banana, fruit fly, vinegar fly) as genetic material discovered sex linkage and criss cross inheritance; genes are locted in the chromosomes.

Muller- Father of Actinobiology, effect of radiations/X-rays on Drosophila.

Miescher- Isolated nuclein from nuclei of WBC in pus cells. This nuclein was later on found to be DNA.

Meselson and Stahl- proved that DNA replicates in semiconservative manner by using density gradient centrifugation technique.

Mc Clung- X-bodies observed by Henking in insect sperms was identified as sex chromosome.

Mendel, "The Father of Genetics"- carried out experiments on garden pea (Pisum sativum) to study the inheritance of the factors (now called genes).

Nilsson-Ehle- In 1909, they investigated the inheritance of Kernel Colour in wheat.

Nirenberg - He attempted to find out the spelling of a codon. He showed that uracil (UUU) codes for phenylalamine. Nirenberg and Mathael discovered genetic code and proved experimentally that genetic code is triple in nature: UUU was first codon deciphered by him.

Norman Borlaugh- Developed triple dwarf mexican varieties of wheat.

Ochoa - in vitro synthesis of ribonucleotides and RNA; RNA polymerase enzyme.

Punnett-Checker board method to solve mendelian problems. He along with Bateron worked on gene interaction by using sweet pea.

Paul Berg- Father of Genetic Engineering. He transplanted gene of SV 40 virus in E. coll and developed a hybrid organism.

Robert Holly-The first person to determine the base sequence of a tRNA molecule.

S.H. Kim-In 1973, proposed the three-dimension structure of tRNA.

Strasburger- introduced the term 'polyploid' in 1910.

Seth Wright- a New England farmer first saw mutations in 18th century in male Ancon Sheep.

Stern- Cytological proof of crossing over.

Sutton- Concept of gene

Sutton and Boveri- Chromosome theory of inheritance.

Temin and Baltimore- discovered reverse central dogma.

(RNA → DNA → RNA → Protein) RNA shows reverse transcription in retroviruses.

Taylor- Chromosomes replicate in semiconservative manner.

Tjio and Levan (1956) reported correct number of human chromosomes i.e., 2N = 46 = 23 (22 pairs of autosomes and one pair of sex chromosomes).

W. Waldeyer- introduced the term 'chromosome' in 1988. W. Flemming coined the term chromatin in 1879.

Weismann- Continuity of germ plasm theory.

Watson and Crick- Double helical molecular model of DNA.

Wilkins and Franklin-X-ray Crystallography of DNA and showed that a molecule of DNA has 2 spirally coiled strands with a diameter of 20A.

Wilson and Stevens- Chromosome theory of sex determination; term X and Y chromosome for sex

chromosomes.

Yanofsky-Modified one gene one enzyme theory to one cistron one polypeptide theory.