Chapter 4: Molecular biology in medicine

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Chapter 4 Molecular biology in medicine

• Inherited diseases also known as genetic
  disorders, exist because of some defect in kind
  or amount of DNA in the affected person.

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Chapter 4 Molecular biology in medicine

• Inherited diseases also known as genetic
  disorders, exist because of some defect in kind
  or amount of DNA in the affected person.
• Testing new born babies allows doctors to
  discover if the child has an inherited disease.
  3 diseases are tested for

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Chapter 4 Molecular biology in medicine

• Inherited diseases also known as genetic
  disorders, exist because of some defect in kind
  or amount of DNA in the affected person.
• Testing new born babies allows doctors to
  discover if the child has an inherited disease.
  3 diseases are tested for
• Hypothyroidism (improper functioning of the
  thyroid gland. It can cause impaired growth and
  brain development)

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Chapter 4 Molecular biology in medicine

• Inherited diseases also known as genetic
  disorders, exist because of some defect in kind
  or amount of DNA in the affected person.
• Testing new born babies allows doctors to
  discover if the child has an inherited disease.
  3 diseases are tested for
• Hypothyroidism (improper functioning of the
  thyroid gland. It can cause impaired growth and
  brain development)
• Galactosaemia (lacking the enzyme that
  metabolises galactose causing death)

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Chapter 4 Molecular biology in medicine

• Inherited diseases also known as genetic
  disorders, exist because of some defect in kind
  or amount of DNA in the affected person.
• Testing new born babies allows doctors to
  discover if the child has an inherited disease.
  3 diseases are tested for
• Hypothyroidism (improper functioning of the
  thyroid gland. It can cause impaired growth and
  brain development)
• Galactosaemia (lacking the enzyme that
  metabolises galactose causing death)
• Cystic Fibrosis (abnormal secretions that have a
  serious effect on the function of lungs and
  digestion)

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Chapter 4 Molecular biology in medicine

• Phenylketonuria (PKU) suffers cannot metabolise
  the amino acid phenylalanine to tyrosine. The
  build up causes brain damage and with early
  detection, the baby can develop normally.

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Chapter 4 Molecular biology in medicine

• Gene therapy is a medical procedure that modifies
  the genetic material of living cells of an
  individual so that a genetic defect is corrected.

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Chapter 4 Molecular biology in medicine

• Gene therapy is a medical procedure that modifies
  the genetic material of living cells of an
  individual so that a genetic defect is corrected.
• There are 2 broad categories
• In vivo (given directly to the patient)
• Ex vivo (a patients cells are manipulated
  outside the body and then returned into the
  individual)

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Chapter 4 Molecular biology in medicine

• Gene therapy is a medical procedure that modifies
  the genetic material of living cells of an
  individual so that a genetic defect is corrected.
• There are 2 broad categories
• In vivo (given directly to the patient)
• Ex vivo (a patients cells are manipulated
  outside the body and then returned into the
  individual)
• Vectors are used to carry the gene into a cell,
  the most commonly used vectors are modified
  viruses.

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Chapter 4 Molecular biology in medicine

• The genetic material of viruses varies some have
  DNA and some have RNA

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Chapter 4 Molecular biology in medicine

• The genetic material of viruses varies some have
  DNA and some have RNA
• Viruses that have DNA replicate in the nucleus of
  the cell they infect. Viruses with RNA generally
  replicate in the cytoplasm of cells they infect.

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Chapter 4 Molecular biology in medicine

• The genetic material of viruses varies some have
  DNA and some have RNA
• Viruses that have DNA replicate in the nucleus of
  the cell they infect. Viruses with RNA generally
  replicate in the cytoplasm of cells they infect.
• An exception to the rule are retroviruses. They
  are RNA viruses that replicate in the nucleus.

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Chapter 4 Molecular biology in medicine

• The genetic material of viruses varies some have
  DNA and some have RNA
• Viruses that have DNA replicate in the nucleus of
  the cell they infect. Viruses with RNA generally
  replicate in the cytoplasm of cells they infect.
• An exception to the rule are retroviruses. They
  are RNA viruses that replicate in the nucleus.
• Retroviruses are useful for cells as they can be
  taken and cultured outside the body e.g. blood or
  bone marrow cells.

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Chapter 4 Molecular biology in medicine

• The genetic material of viruses varies some have
  DNA and some have RNA
• Viruses that have DNA replicate in the nucleus of
  the cell they infect. Viruses with RNA generally
  replicate in the cytoplasm of cells they infect.
• An exception to the rule are retroviruses. They
  are RNA viruses that replicate in the nucleus.
• Retroviruses are useful for cells as they can be
  taken and cultured outside the body e.g. blood or
  bone marrow cells.
• Because the cloned gene is incorporated into the
  chromosome, when the cell undergoes further
  mitosis the cloned genetic material replicates
  along with the remainder of the chromosome into
  which it is inserted.

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Chapter 4 Molecular biology in medicine

• Adenoviruses are DNA viruses which enters the
  nucleus but remains separate from the host DNA.
  The small piece of free DNA that is produced
  does not replicate therefore the next generation
  of cells lack the vital gene.

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Chapter 4 Molecular biology in medicine

• Gene therapy is a procedure with the potential to
  correct some genetic defects.

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Chapter 4 Molecular biology in medicine

• Gene therapy is a procedure with the potential to
  correct some genetic defects.
• Gene therapy involves inserting a functional
  piece of DNA into the cells of an individual with
  a genetic defect.

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Chapter 4 Molecular biology in medicine

• Gene therapy is a procedure with the potential to
  correct some genetic defects.
• Gene therapy involves inserting a functional
  piece of DNA into the cells of an individual with
  a genetic defect.
• Virus vectors are commonly used to carry DNA into
  other cells.

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Chapter 4 Molecular biology in medicine

• Different genetic conditions can develop at
  different ages in individuals.

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Chapter 4 Molecular biology in medicine

• Different genetic conditions can develop at
  different ages in individuals.
• Tests exist to distinguish functional from
  non-functional segments of DNA in an individual.

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Chapter 4 Molecular biology in medicine

• Different genetic conditions can develop at
  different ages in individuals.
• Tests exist to distinguish functional from
  non-functional segments of DNA in an individual.
• In these tests, the DNA of one individual is
  often compared with the DNA of other family
  members.

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Chapter 4 Molecular biology in medicine

• Different genetic conditions can develop at
  different ages in individuals.
• Tests exist to distinguish functional from
  non-functional segments of DNA in an individual.
• In these tests, the DNA of one individual is
  often compared with the DNA of other family
  members.
• Tests can determine whether or not the tested
  individual has a particular condition or is
  likely to develop the condition.

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Chapter 4 Molecular biology in medicine

• If we understand the mechanism by which an
  infective organism or agent causes disease, we
  may be able to design a drug to prevent it
  occurring.

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Chapter 4 Molecular biology in medicine

• If we understand the mechanism by which an
  infective organism or agent causes disease, we
  may be able to design a drug to prevent it
  occurring.
• One of the proteins, an enzyme, on the outer
  layer of the influenza virus has a non-variable
  active site that is important for the
  continuation of their life cycle.

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Chapter 4 Molecular biology in medicine

• Vaccinations contain antigens from
  disease-causing organisms that stimulate the
  immune system to develop antibodies for future
  protection from the disease.

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Chapter 4 Molecular biology in medicine

• Vaccinations contain antigens from
  disease-causing organisms that stimulate the
  immune system to develop antibodies for future
  protection from the disease.
• It is difficult to make vaccines against some
  parasites because of the complexity of the life
  cycle and knowing which of their antigens are
  most important in their disease-causing capacity

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Chapter 4 Molecular biology in medicine

• Vaccinations contain antigens from
  disease-causing organisms that stimulate the
  immune system to develop antibodies for future
  protection from the disease.
• It is difficult to make vaccines against some
  parasites because of the complexity of the life
  cycle and knowing which of their antigens are
  most important in their disease-causing capacity
• Vaccines must generally be refrigerated for
  storage and require trained staff to inject them.

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Chapter 4 Molecular biology in medicine

• Some diseases caused by a deficiency of a
  particular protein can be treated with a
  genetically engineered (GE) form of the protein.

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Chapter 4 Molecular biology in medicine

• Some diseases caused by a deficiency of a
  particular protein can be treated with a
  genetically engineered (GE) form of the protein.
• GE proteins are produced by bacteria carrying GE
  plasmids

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Chapter 4 Molecular biology in medicine

• Some diseases caused by a deficiency of a
  particular protein can be treated with a
  genetically engineered (GE) form of the protein.
• GE proteins are produced by bacteria carrying GE
  plasmids
• Nanoparticles have been designed to carry and
  deliver drugs to cancer cells.

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THE END