Danica Roem makes her pitch to voters at the Bull Run Swim & Raquet Club in Manassas on June 2. (J. Lawler Duggan/For The Washington Post)

The Sept. 27 Metro article "Gender identity at the fore in Va. contest" reported that Del. Robert G. Marshall (R-Prince William) refused to acknowledge his opponent, Danica Roem (D), as a woman. Mr. Marshall was quoted by a reporter from the Prince William Times as saying, "Why do you call Danica a woman? Did Danica's DNA change?" and was further quoted as saying, "You can change your appearances, but your DNA fixes your bodily structures for your entire life," apparently basing his statement on "research" he conducted at the National Library of Medicine. I doubt it has Ms. Roem's or anyone else's DNA on file.

Even if it did and the DNA showed a Y chromosome, there are many other factors involved. Was the SRY (sex-determining region of the Y) fully active? What is the ratio of estradiol and dihydrotestosterone, the most active female and male hormones, respectively? These are steroids that differ by only one methyl group and show some cross-reactivity with their nuclear receptors.

Beyond the development of anatomy and the associated physiology is the more complex issue of gender self-perception. Just ask a physician whose practice includes working with transgender people. I met Ms. Roem and never would have guessed that she is a transgender person if she had not stated it in a public forum. By every measure she comes across as a woman, and if that is how she looks and feels, who is Mr. Marshall to question it?

Douglas A. Eagles, Woodbridge