Molecular Biology/Genetics USMLE Step 1 Practice Question
A 25-year-old male and his wife go to a fertility clinic for evaluation. His wife has no significant past medical history and is given a 'clean bill of health.' He has had bronchiectasis and a history of recurrent sinusitis, and was diagnosed with situs inversus as a child. He is found to be sterile. What is the most likely cause of his infertility?
Answer choices
- AAbnormal levels of sphingomyelinase
- BHexosaminidase A deficiency
- CAbnormal structure of ciliaCorrect answer
- D47,XXY karyotype
- EFibrillin deficiency
- FCystic fibrosis transmembrane conductance regulator mutation
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