Comma and dash introducing a list

Question

Is it right to put a comma before the dash that introduces a series?

As the mentor of the original five interns, — Meredith, Cristina, Alex, the runaway Izzie, and the now dead George — Dr. Bailey...

Answer 1

Logically, the comma should go after the dashes, since it separates the prepositional phrase from the main part of the sentence, and the names enclosed in dashes are part of the prepositional phrase.

However, to many people (myself included), a dash followed by a comma just looks awkward and inelegant, and it might even cause them to stumble in their reading.

Removing the comma is an acceptable option and a matter of style and consistency; but to me, sentence-initial prepositional phrases as long as yours that are not separated from the main sentence with a comma are just as awkward.

Rather than fiddling with where or whether to put the comma, I would suggest simply substituting parentheses for the dashes. The meaning is almost the same—close enough, anyway—and commas are not awkward following parentheses:

As the mentor of the original five interns (Meredith, Cristina, Alex, the runaway Izzie, and the now dead George), Dr. Bailey was …

Answer 2

Just remove the comma. The em-dashes do the work of separating off the appositive phrase (listing the interns) which commas would otherwise do.