Multiple choice

A protein coded by a tumour suppressor gene in humans is

  1. the protein, which helps prevent apoptosis

  2. the protein, which codes for a DNA repair enzyme

  3. the protein, which controls progression through the cell cycle

  4. the protein, which forms fractions of a growth factor signalling pathway

  5. acts in the degradation of CD4 in the endoplasmic reticulum
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Tumour suppressor genes code for proteins, which normally control progression through a cell cycle checkpoint. These genes only contribute to a cancer when both copies are mutated in a way, which produces an inactive protein product. A single mutation inactivating one gene only has no effect. They contribute to cancer because the absence of the protein product removes controls on cell division.

Keep practicing — related questions