Before she retired in 2003, Meredith and her research group pioneered the use of DNA typing to differentiate Vitis vinifera grape varieties and for elucidating their parentage, which gives insight into the varieties' history and place of origin. In 1996, Meredith and her research established the parentage of Cabernet Sauvignon, which was the first application of such techniques. Later, Chardonnay, Syrah, and Zinfandel followed. The research group showed that the varieties Zinfandel, Primitivo, and Crljenak Kaštelanski are identical. The varieties Charbono and Corbeau were also found to be identical.
In 2009, she was inducted into the Vintners Hall of Fame.
In 1986, she moved to Napa Valley commuting to UC Davis where her husband, Steve Lagier, made wine at Robert Mondavi Winery. After her retirement from academia in January 2003, Meredith and her husband grow on 4 acres Syrah, Zinfandel, Malbec, and Mondeuse in the Mount Veeder AVA of Napa Valley under the Lagier-Meredith label. The first vines on their property were planted in 1994.
- Lagier-Meredith: Who we are Archived August 21, 2008, at the Wayback Machine
- "Researchers Discover Zinfandel's Hidden Roots". UC Davis. 2002-09-03.
- USA, Slow Food. "Ark of Taste". Slowfood USA. Archived from the original on 2008-07-06. Retrieved 2006-07-30.
- "Grape Geneticist Dr. Carole Meredith On Her Life Among the Vines - Grapecollective.com". grapecollective.com. Retrieved 2015-12-15.
- vinagency.com, Vin. "Lagier Meredith - A Small Mountain Vineyard". lagiermeredith.com.