Brad and Rocky drink equivalent amounts of alcohol (and have the same body mass) would you
predict that Brad\'s levels of acetaldehyde are higher or lower when compared to Rocky? Explain
your answer. Brad: Fast ADH; Slow ALDH Rocky: Fast ADH; Fast ALDH High levels of
acetaldehyde make drinking unpleasant, resulting in facial flushing, nausea, and a rapid
heartbeat. With all other environmental and genetic factors being equal, Rocky is at higher risk
for alcoholism than Brad. Explain this statement.
Solution
Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are enzymes involved in
the metabolism of alcohol. ADH catalyses the conversion of ethanol to acetaldehyde. ALDH
converts acetaldehyde to acetate.
Brad has Fast ADH, so he would have rapid production of acetaledehyde from the consumed
ethanol. Because he also has slow ALDH, the produced acetaldehyde would not be properly
converted into acetate. This could lead to accumulation of acetaldehyde. As levels of
acetaldehyde increases, there are various unpleasant consequences, and this should discourage
Brad from drinking further.
Rocky, on the other hand, has fast ADH and fast ALDH. In his body, ethanol is metabolized
more quickly. As acetaldehyde is produced by ADH, it is rapidly converted into acetate by fast
ALDH. Since there is no accumulation of acetaldehyde, we can expect Rocky to drink more.
Therefore, Rocky is at higher risk for alcoholism than Brad.
predict that Brad\'s levels of acetaldehyde are higher or lower when compared to Rocky? Explain
your answer. Brad: Fast ADH; Slow ALDH Rocky: Fast ADH; Fast ALDH High levels of
acetaldehyde make drinking unpleasant, resulting in facial flushing, nausea, and a rapid
heartbeat. With all other environmental and genetic factors being equal, Rocky is at higher risk
for alcoholism than Brad. Explain this statement.
Solution
Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are enzymes involved in
the metabolism of alcohol. ADH catalyses the conversion of ethanol to acetaldehyde. ALDH
converts acetaldehyde to acetate.
Brad has Fast ADH, so he would have rapid production of acetaledehyde from the consumed
ethanol. Because he also has slow ALDH, the produced acetaldehyde would not be properly
converted into acetate. This could lead to accumulation of acetaldehyde. As levels of
acetaldehyde increases, there are various unpleasant consequences, and this should discourage
Brad from drinking further.
Rocky, on the other hand, has fast ADH and fast ALDH. In his body, ethanol is metabolized
more quickly. As acetaldehyde is produced by ADH, it is rapidly converted into acetate by fast
ALDH. Since there is no accumulation of acetaldehyde, we can expect Rocky to drink more.
Therefore, Rocky is at higher risk for alcoholism than Brad.
