Chromosome Abnormalities

There are many different types of chromosome abnormalities that require clinical care by a physician or other healthcare professional. Listed in the directory below are some, for which we have provided a brief overview.

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More Information

• Overview of Chromosome Abnormalities
• Types of Chromosome Abnormalities
• Numerical Abnormalities: Overview of Trisomies and Monosomies
• Down Syndrome
• Trisomy 18 & 13
• Turner Syndrome
• Structural Abnormalities: Deletions (Cri du Chat) and Duplications (Pallister Killian)
• Translocations
• Translocation Down Syndrome
• Other Arrangements: Rings and Inversions
• Mosaicism
• Mosaic Down Syndrome
• How Chromosome Abnormalities Happen: Meiosis, Mitosis, Maternal Age, Environment
• Chance a Chromosome Abnormality Will Occur Again: Numerical, Structural (Inherited and De Novo), Mosaicism