Scene II: Will Alan ever play for the Lakers

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Scene II Will Alan ever play for the Lakers?

• After this lesson, the students will be able to
• Explain x-linked inheritance using Factor VIII
  deficiency (hemophilia) as an example
• Describe the treatment for hemophilia
• Explain the importance of early diagnosis and
  carrier testing of hemophilia and
• Describe some societal issues associated with
  hemophilia and its treatment.

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Alans Situation

• Alan suffers a painful knee injury while shooting
  baskets in his parents driveway. Examination at
  the emergency room indicates that Alan has a bad
  sprain, in addition to bleeding within the knee
  joint. Further testing reveals a deficiency of
  Factor VIII, and a diagnosis of classical
  hemophilia is made. Stacy is found to have
  reduced Factor VIII levels, consistent with her
  being a hemophilia carrier.

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Alans Situation (contd.)

• Following referral for genetic counseling, Paul
  and Stacy understand that the gene for Factor
  VIII is on the X-chromosome. Since Stacy has two
  X-chromosomes, only half are unable to make
  usable Factor VIII. The other half make all of
  the clotting factor that she needs. But Alan
  happened to inherit from her the X-chromosome
  unable to make Factor VIII. Because his other sex
  chromosome is a Y, he has no back up gene for
  Factor VIII. Until his basketball accident, the
  deficiency went unnoticed.

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What is Hemophilia?

• AKA Factor VIII deficiency
• Blood clotting disorder usually affecting males
• 1 in 5,000
• Abnormal protein Factor VIII created
• Factor VIII necessary for blood clotting
• Clotting takes longer
• Severity varies based on amount of Factor VIII
  produced
• X-linked disorder (found on X chromosome)

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Hemophilia Testing

• Testing for Factor VIII
• Blood samples taken and amount of Factor VIII
  analyzed

• Testing for Carriers and Prenatal Testing
• DNA analyzed for gene mutation

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Treatments

• Factor VIII Replacement
• Intravenous injections of Factor VIII
• Causes proteins to help clotting
• Joint Replacement
• Knee, hip, ankle replacement if arthritis is
  severe
• Regular exercise for strong muscles to protect
  the weak joints

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Alans Situation

• Alan is starting on Factor VIII home infusion.
  His parents are taught how to inject Alan with
  Factor VIII that has been removed from pooled,
  donated blood, purified and packaged for ready
  use. The Factor VIII concentration can be kept at
  home and prepared for injection only when Alan
  feels that bleeding has occurred. The
  concentration can also be taken with them on
  trips.

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Factor VIII Infusions

• Objective replace missing clotting factor
• When used
• Used at time of bleeding to prevent tissue damage
• Prior to and during surgery
• Cost over 100,000/year (beyond lifetime cost of
  most insurance plans)
• Prior to 1984 HIV prevalent in the Hemophilia
  community (70-90)

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Alans Situation

• After the increased risk of hepatitis is
  discussed, immunizations against Hepatitis B and
  D are scheduled. Stacy is concerned about
  hemophilia and AIDS. She is assured that while
  AIDS was a threat to hemophiliacs receiving
  pooled Factor VIII years ago, more strict donor
  guidelines and heat-treating of pooled blood
  reduces the chances of AIDS being a problem for
  hemophiliacs. Stacy and Paul are reassured. Yet
  Paul adds, But lets see if our insurance will
  pay for the recombinant Factor VIII.

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Alans Situation

• Stacy recalls that about a year ago, a boy in
  Franks school was discovered to be HIV positive,
  presumably from contaminated blood with which he
  was transfused during heart surgery. Several
  parents demanded that the boy be removed from
  school, threatening to remove their own children
  if their demands were not met. Stacy remembered
  following the issue in the newspapers. She
  remembered that the boy and his family moved out
  of state before the school board or disgruntled
  parents took any action. At the time, she took no
  particular position on the issue. What must it
  have been like for the boy and his family?

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Expanding the Chance Family

• Stacy, since hemophilia is X-linked and youre a
  carrier, its important that we contact other
  family members of yours to discuss their risk of
  being carriers. Do you have any sisters?
  inquires the genetic counselor.
• Yes, one. And a brother, David.
• Your sister might also be a carrier. You should
  bring her up to date on this and ask her to make
  an appointment with us.
• Stacy refuses. And if you tell her anything
  about Alans hemophilia, Ill sue you and this
  place for everything youre worth.

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Essay 2

• Compare and contrast the treatment of PKU and of
  hemophilia.

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