Transcript Introduction to Genetics Klug 8th Edition

DVD- Cracking the Code- DeCode and
Iceland
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Controversy in Iceland
A. deCODE a biotechnology company
may use health, genealogical, and
genetic information of 270,000
residents.
B. Why did deCODE choose Iceland?
Low genetic diversity in the population
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Successes: ID of genes for various
diseases
Problem: Privacy is in jeopardy
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1866 Mendel’s work is published
1886 Advances in microscopes=chromosomes
1880’s 1890’s Mitosis/meiosis
1900 Correns confirms Mendel’s work
early1900’s Sutton and Boveri-Chromosome
Theory of Inheritance
Early 1900’s Mutations discoveries led to gene
mapping
1920’s-1940’s Avery, McLeod, McCarty –DNA
carries information
1952-Watson and Crick-double helix
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Mendel is the starting point for Genetics (the
study of heredity and variation)
1860’s used garden peas
Identified patterns of inheritance
His work was ignored until Correns in 1900’s
confirmed his work
Genes (units of inheritance)occur in pairs and
control traits
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Chromosome numbers in sexual reproduction
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Diploid number (2n)- 46 for humans
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Homologous chromosomes – one set from
Mom and one set from Dad (23 each for
humans)
Haploid number (n)- 23 for humans
Sutton and Boveri –Chromosome Theory of
Inheritance = genes are carried on
chromosomes
 Fruity Fly studies led to discoveries:
 Terms:
Mutation (inherited change in gene)
Allele (alternate forms of a gene)
Phenotype (observable features of genes)
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Until 1940’s proteins were thought to be the
source of genetic material
Proteins are abundant in the cell and are
diverse in structure and function BUT
Fruit Flies, bacteria, and viruses led to the
discovery that DNA
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Alphabets (Genetic Code)
DNA is made of nucleotides (A,T, G, C)
RNA is made of nucleotides (A, U, G, C)
Watson and Crick-double helix with
complimentary relationships
A-T(U) G-C
Transcription- DNA to RNA
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Translation- RNA to protein
Central Dogma
of Genetics