Question

Kuzumaki et al. (2011) found that messenger RNA levels for the BDNF gene became greater after a few weeks in mice who were living in an enriched environment compared to mice who were living in an impoverished environment. This is an example of:

1) Gene expression
2) Epigenetics
3) Neuroplasticity
4) Behavioral genetics

Answer 1

The study by Kuzumaki et al. (2011) showing increased BDNF mRNA levels in mice living in enriched vs. impoverished environments exemplifies epigenetics, where the environmental context leads to heritable changes in gene expression without DNA sequence alteration.

Step-by-step explanation:

Kuzumaki et al. (2011) found that messenger RNA levels for the BDNF gene increased in mice living in enriched environments, which is an example of epigenetics. This phenomenon is where gene expression is modified, not by changes in the DNA sequence, but by environmental factors. The increase in BDNF mRNA levels indicates that the neuronal environment can induce heritable changes in gene expression that impact the physiology and behavior of the mice.

Epigenetics involves changes to the transcriptional potential of genes without altering the underlying DNA sequence. These changes can result from various factors, including environment, life experiences, and even social interactions. In the case of the mice, the enriched environment led to increased expression of BDNF, a gene implicated in neuroplasticity, the brain's ability to reorganize and form new neural connections. This can also correlate with better learning and memory processes. Such findings underscore the significance of environmental factors in regulating gene expression and the potential for these changes to be inherited by future generations.