Blood and immunity: Wiskott-Aldrich syndrome: practice question

A Physiology question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

Try it

Physiology · Blood and immunity: Wiskott-Aldrich syndrome

Sample item

A 2-year-old boy has eczema, recurrent ear infections and bleeding with a low platelet count and unusually small platelets. A mutation in a protein regulating which cellular structure is responsible?

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

B. Actin cytoskeleton

Wiskott-Aldrich syndrome is an X-linked disorder of the WAS protein, which organises the actin cytoskeleton in haematopoietic cells. This impairs platelet formation, T cell function and immune synapse formation, causing the triad of thrombocytopenia with small platelets, eczema and infections.

Option by option

  • A. Microtubules

    Microtubule and dynein defects cause disorders such as Kartagener syndrome, not this triad.

  • B. Actin cytoskeleton (correct)

    Correct. The WAS protein regulates actin polymerisation in blood cells.

  • C. Intermediate filaments

    Intermediate filaments such as keratin are not the defect in this syndrome.

  • D. Nuclear lamina

    Nuclear lamina defects cause laminopathies, not this triad.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

More Physiology questions

Questions about this Physiology question

What is the answer to this Physiology question?

The best answer is B, Actin cytoskeleton. Wiskott-Aldrich syndrome is an X-linked disorder of the WAS protein, which organises the actin cytoskeleton in haematopoietic cells.

Why is "Microtubules" not the answer?

Microtubule and dynein defects cause disorders such as Kartagener syndrome, not this triad.

Why is "Intermediate filaments" not the answer?

Intermediate filaments such as keratin are not the defect in this syndrome.

Why is "Nuclear lamina" not the answer?

Nuclear lamina defects cause laminopathies, not this triad.

What concept does this question test?

It tests Blood and immunity: Wiskott-Aldrich syndrome in Physiology. This impairs platelet formation, T cell function and immune synapse formation, causing the triad of thrombocytopenia with small platelets, eczema and infections.

How hard is this question?

We tag it as a multi-step question: it asks you to combine more than one idea. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Blood and immunity: Wiskott-Aldrich syndrome?

For each system, sketch the key graph (pressure–volume loop, oxygen dissociation curve, nephron handling) and explain it aloud. Then use the flashcards and the other Physiology questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.