A 24-year-old woman arrives at the office with a fresh mole on her right leg. She is concerned that it is skin cancer because she has used tanning beds many times a year since she was 18. Physical examination reveals a 5-mm dark, round macule with homogenous hue and distinct boundaries on her front thigh. The lesion is deeper in color than the other moles. She is diagnosed with a benign acquired melanocytic nevus after a biopsy of the lesion reveals normal-appearing nevus cells grouped in the epidermis. During histologic examination, her epithelial cells are discovered to have a condensed body composed of extensively methylated DNA near the nucleus's periphery. This region of DNA is most likely associated with which of the following genetic findings?

Question

Quizplus · Accepted Answer

Eductional Objective: In genetically normal females, X-inactivation occurs, resulting in the conversion of the inactivated X chromosome into compact heterochromatin (Barr body). Heterochromatin is a kind of condensed chromatin that is made up of extensively methylated DNA that is tightly bound to deacetylated histones. It has very little transcriptional activity. Euchromatin, on the other hand, is loosely organized and has a high amount of transcriptional activity.

A 24-Year-Old Woman Arrives at the Office with a Fresh