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  1. Home/
  2. Quick Facts: Children's Health Issues/
  3. Chromosomal and Genetic Abnormalities/
    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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