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Merck Manual
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MEDICAL TOPICS
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Pediatrics
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Chromosome and Gene Abnormalities
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Chromosome and Gene Abnormalities
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Overview of Chromosomal Abnormalities
Terminology
Diagnosis
Screening
Screening reference
Down Syndrome (Trisomy 21)
References
Etiology
Etiology references
Pathophysiology
Pathophysiology references
Symptoms and Signs
General appearance
Growth and development
Cardiac manifestations
Gastrointestinal manifestations
Diagnosis
Concomitant medical conditions
Diagnosis references
Treatment
Key Points
More Information
Trisomy 18
General references
Symptoms and Signs
Diagnosis
Diagnosis reference
Treatment
Screening for complications of trisomy 18
Treatment reference
Prognosis
Prognosis references
More Information
Trisomy 13
General reference
Diagnosis
Diagnosis reference
Treatment
Prognosis
Prognosis reference
More Information
Chromosomal Deletion Syndromes
5p- syndrome (5p minus syndrome or cri-du-chat syndrome)
4p- syndrome (4p minus syndrome or Wolf-Hirschhorn syndrome)
Subtelomeric deletions
Microdeletion and Microduplication Syndromes
Overview of Sex Chromosome Abnormalities
Lyon hypothesis (X-inactivation)
Reference
Turner Syndrome
General references
Pathophysiology
Symptoms and Signs
Symptoms and signs references
Diagnosis
Concomitant medical conditions
Diagnosis reference
Treatment
Treatment reference
Key Points
Klinefelter Syndrome (47,XXY)
Reference
Diagnosis
Treatment
47,XYY Syndrome
Other X Chromosome Abnormalities
Reference
Fragile X Syndrome
Reference
Symptoms and Signs
Diagnosis
Treatment
More Information