Her father was a biochemistry professor at the University of Alaska Fairbanks and her Mexico-born mother was a language teacher.

[1] She began her vocal studies as a young girl with American dramatic soprano Dorothy Dow.

Genaux began her professional career specializing in charming portrayals of Rossini comic heroines (Rosina in Il barbiere di Siviglia, Isabella in L'italiana in Algeri, Angelina in La Cenerentola).

She has performed these roles more than two hundred times with many of the major U.S. opera companies (including the Metropolitan, San Francisco, Dallas, Seattle, San Diego, Pittsburgh, and Minnesota Operas), as well as in Paris, Vienna, Berlin, Amsterdam, Dresden, Munich, Montreal, Tel Aviv, Verona, Santiago and Perth.

Prior career highlights have included: Brussels (La Monnaie) and Paris (Champs-Elysées) for Hasse's Marc'Antonio e Cleopatra, led by long-time mentor, conductor René Jacobs; the recently rediscovered Alessandro Scarlatti oratorio La Santissima Trinità in Paris, Palermo and Lyon, which marked her first collaboration with Fabio Biondi and his Europa Galante; Gluck's Orfeo ed Euridice at the Los Angeles Opera; a Weill Hall recital at New York's Carnegie Hall;[2] Rosinas at the Deutsche Staatsoper Berlin, Vienna State Opera and the Metropolitan Opera; the Opéra National de Paris (Barbiere and Alcina); a concert at the Deutsche Staatsoper Berlin with René Jacobs and the Akademie für Alte Musik performing music from their "Arias for Farinelli" CD; Mendelssohn's A Midsummer Night’s Dream in Paris and Hong Kong with Kurt Masur and the Orchestre National de France; Rinaldo in Montpellier and Innsbruck; Minnesota Opera for Lucrezia Borgia, I Capuleti e i Montecchi and Semiramide; Urbain in Les Huguenots for the opening of the new opera house in Bilbao; Hassem in Donizetti's Alahor in Granata in Seville; Selimo in Hasse's Solimano at the Deutsche Staatsoper Berlin; Juno/Ino in Handel's Semele at New York City Opera; and seven appearances at the Caramoor Festival.