GST 3100 Genetic and Agriculture Biotechnology

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GST 3100Genetic and Agriculture Biotechnology

• Lecturer
• Puan Ramisah Mohd Shah
• Depart. of Agrotechnology
• Faculty of Agrotechnology and Food Science

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G. E. N. E. T. I. C.

• The study of heredity.
• (kajian mengenai perwarisan)

BIOTECHNOLOGY
Technologies that involve the use of living
organisms, or products from living
organisms (teknologi yang melibatkan penggunaan
organisma hidup atau produk/hasil dari organisma
hidup)
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Topic 2Mendelian Inheritance

• At the end of the lecture student will be able
• To understand 2 Mendels rules of inheritance.
• To define the some of important genetic terms.

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Topic 2 Mendelian Inheritance

• Gregor Johann Mendel
• Father of genetics
• Experiment Pea Plants (Pisum sativum)
• 3 reason choose this plant

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Seven traits of Pea plants
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How Mendel cross-fertilized two different pea
plants
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Mendels Rules of Inheritance

• Rules of Segregation
• Independent Assortment

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1st Mendel rule Rule of Segregation

• The alleles of a gene exist in pairs but when
  gametes are formed, the members of each pair pass
  into different gametes. Thus each gamete contains
  only one allele of each gene.
• - Monohybrid crossing

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Mendels cross between round and wrinkled seeds
of pea plant.
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Testing the rule of segregation

• Progeny testing
• - self fertilizing F2 individuals
• Testcross
• - cross of any organism with a recessive
  homozygote
• Backcross
• - cross of a progeny with an individual that
  has a parental genotypes

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2nd Mendel rule Independent Assortment
The two different genes will randomly assort
their alleles during the formation of haploid
reproductive cells. - Dihybrid/multihybrid
crossing
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A Punnet Square Regional Punnet

• Write down the genotypes of both parents.
• Write down the possible gametes that each parent
  can make.
• First, you must create an empty Punnett square.
• Fill in the possible genotypes of the offspring
  by combining the alleles of the gametes in the
  empty boxes.
• Determine the relative proportions of genotypes
  and phenotypes of the Punnett square.

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Testing Multihybrids(dihybrid, trihybrid.)

• Rules

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Glosary 1

• Genes
• Definition Units of heredity information that
  consists of DNA and are located on chromosomes.
  Genes can exist in alternative forms called
  alleles.
• Allele
• Definition An alternative form of a gene (one
  member of a pair) that is located at a specific
  position on a specific chromosome. For example,
  the gene for seed shape in pea plants exists in
  two forms, one form or allele for round seed
  shape (R) and the other for wrinkled seed shape
  (r).
• Gamete
• Definition A reproductive cell having a single
  set of chromosomes, especially a mature sperm or
  egg.
• Monohybrid Cross
• Definition is the inheritance of a single pair
  of contrasted characteristics. The system often
  represents dominant characteristics with a
  capital letter, A, where recessive
  characteristics are represented by a lower case
  letter, a.

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Glosary 2

• True-breeding Plant/Line
• Definition A plant, that when self-fertilized,
  only produces offspring with the same traits. The
  alleles for these types of plants are homozygous.
• Hybrids
• Definition The progeny produced by crossing
  organisms that exhibit different inherited traits
  eg. Tall versus dwarf trait

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Glosary 3

• Genotype
• Definition The gene combination it possesses.
• Genotypes comes in two general classes
  homozygotes and heterozygotes.
• Phenotype
• Definition An organism's expressed physical
  traits.
• Heterozygous
• Definition Having two different alleles for a
  single trait.
• For example, the gene for seed shape in pea
  plants exists in two forms, one form or allele
  for round seed shape (R) and the other for
  wrinkled seed shape (r). A heterozygous plant
  would contain the following alleles for seed
  shape (Rr).
• Homozygous
• Definition Having identical alleles for a single
  trait.For example, the gene for seed shape in
  pea plants exists in two forms, one form or
  allele for round seed shape (R) and the other for
  wrinkled seed shape (r). A homozygous plant would
  contain the following alleles for seed shape
  (RR) or (rr).
• F 1
• Definition F is Filial (the latin word) that
  mean progeny.
• Hybrids
• Definition The progeny produced by crossing
  organisms that exhibit different inherited traits
  eg. Tall versus dwarf trait

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Codominance

• A pattern of inheritance in which two alleles are
  both expressed heterozygous condition and
  contribute to the phenotype.

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Incomplete dominance

• A pattern of inheritance in which a heterozygote
  that carries two different alleles exhibits a
  phenotypes that is intermediate to corresponding
  homozygous individuals.

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Overdominance

• Inheritance pattern in which a heterozygote is
  more vigorous than either of the corresponding
  homozygotes.

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Gene Interaction

• When two or more different genes influence the
  outcome of a single trait

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Epistasis

• An inheritance pattern where one gene can mask
  the phenotypic effects of a different gene.