Pathology · single question
Down syndrome is most commonly associated with trisomy of which chromosome?
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Correct answer: B. Chromosome 21
Down syndrome is caused by trisomy 21. Most common chromosomal trisomy compatible with life. Oral findings: macroglossia, fissured tongue, hypodontia, increased perio susceptibility.
- A. Trisomy 18 = Edwards syndrome — overlapping fingers, early death.
- B. CORRECT. Trisomy 21 = Down syndrome. Most common chromosomal abnormality in dental practice.
- C. Trisomy 22 causes cat eye syndrome or Emanuel syndrome — rare.
- D. Trisomy 13 = Patau syndrome — severe; median cleft palate, polydactyly.