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  2. Quick Facts: Children's Health Issues/
  3. Chromosomal and Genetic Abnormalities/
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Chromosomal and Genetic Abnormalities
  • Genes and Chromosomes
    • What are genes?
      • What are genes made of?
    • What are chromosomes?
    • What is a genetic disorder?
    • What causes genetic disorders?
  • Down Syndrome (Trisomy 21)
    • What is Down syndrome?
    • What causes Down syndrome?
    • What are the symptoms of Down syndrome?
    • How can doctors tell if my child has Down syndrome?
    • How do doctors treat Down syndrome?
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