SAO PAULO, Jan 10 (Reuters) - Anec, a Brazilian trade group representing grain exporters, on Tuesday said the country has booked shipments of more than 1 million tonnes of corn to China in January, putting Brazil on course to export a record overall volume in the current month.

Earlier in the day, Anec revised its Brazilian corn exports estimate for January to 5.024 million tonnes, up from 4.326 million tonnes forecast in the previous week, reflecting a surge in sales to China.

Chinese customs authorities updated a list of approved Brazilian corn exporters at the end of last year, a move that jump-started sales of the commodity to the world's second-largest economy.

A potential surge of Brazilian corn exports to China may also reshape global trade flows and result in fewer corn sales from farmers in the United States, the world's top corn supplier. (Reporting by Nayara Figueiredo Writing by Ana Mano; Editing by Chris Reese and Bill Berkrot)