Molecular Biology/Genetics USMLE Step 1 Practice Question
On physical examination, a newborn is found to have micrognathia, a prominent occiput, low-set ears, and rocker-bottom feet. There is very little mental development during the first months of life, and the infant dies of cardiac complications after 8 months. A complete karyotype of this child would most likely show which of the following?
Answer choices
- ATrisomy 18Correct answer
- BXXY
- CTrisomy 21
- D45,X
- ETrisomy 13
- FMonosomy 21
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