Question

The dopamine transporter gene encodes a protein required to re-uptake dopamine into the pre-synaptic neuron from the synapse. How might a variant allele of the dopamine transporter gene, which results in a transporter protein with increased function , be involved in predisposing an individual to addictive behavior?

A) The dopamine transporter variant allele would produce more dopamine in response to addictive behavior

B) The dopamine transporter variant allele would produce less dopamine in response to addictive behavior

C) The dopamine transporter variant allele would remove too much dopamine from the synapse

D) The dopamine transporter variant allele would result in increased dopamine signaling leading to tolerance

E) The dopamine transporter would have low activity leading to high levels of dopamine signaling without the stimulation of addictive behavior

A nonsense mutation occurs in the first exon of the tumor suppressor gene BRCA1. A cell is heterozygous for this mutation, the other BRCA1 allele is wildtype producing a protein with normal function. What is the correct prediction for the state of the cell cycle in this cell?

A) The cell cycle would be normal and the cell would exhibit normal growth and division

B) The cell cycle would slow down and the cell would exhibit decreased growth and division

C) The cell cycle would not stop and the cell would exhibit increased growth and division

D) The cell cycle would stop and the cell would die

Answer 1

1) C. The dopamine transporter variant allele would remove too much dopamine from the synapse.

2) A. The cell cycle would be normal and the cell would exhibit normal growth and division.