The data imply that most odor receptor genes are what?

The data imply that most odor receptor genes are what?

• A. Inactive
• B. Active
• C. Not expressed
• D. Pseudogenes

Answer: (A)

Odor receptor genes are a very large and duplicative gene family, and in many species a large portion of those copies no longer function or get expressed in the olfactory epithelium. The data show that the majority of these genes are not producing functional receptors, meaning they’re inactive in terms of expression and function. Some of these inactive copies are pseudogenes—genomic sequences that resemble genes but are nonfunctional—but the main takeaway the data convey is their lack of activity.

Odor receptor genes are a very large and duplicative gene family, and in many species a large portion of those copies no longer function or get expressed in the olfactory epithelium. The data show that the majority of these genes are not producing functional receptors, meaning they’re inactive in terms of expression and function. Some of these inactive copies are pseudogenes—genomic sequences that resemble genes but are nonfunctional—but the main takeaway the data convey is their lack of activity.