A child has recurrent bacterial infections, absent tonsils and no B cells. Which gene is mutated?
Answer and explanation
Correct answer: A. BTK
- Step 1: X-linked agammaglobulinemia results from BTK mutation. Answer: BTK. Why not the others: ADA causes SCID, CD40L causes hyper-IgM and WAS causes Wiskott-Aldrich.
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