Competition in the 40th Annual Iditarod Trail Sled Dog Race began on Sunday with the official start of the race on a frozen lake about 80 miles north of Anchorage. The 66 mushers and their dog teams dashed away, in two-minute intervals, to launch the timed competition in the race to Nome. From sun-dappled Willow Lake, they began their trek through about 1,000 miles of roadless Alaska wilderness. Some sled-dog racing family dynasties were on display at the event, with Ray Redington Jr., grandson of Iditarod founder Joe Redington, the first out of the starting chute on Willow Lake. His brother, Ryan Redington, was the last to depart. Last year\'s fourth-place finisher, 25-year-old Dallas Seavey, departed one spot ahead of his father, 2004 race champion Mitch Seavey. Following behind them was family patriarch Dan Seavey, who raced in the first Iditarod in 1973 and wore a special bib number of 100 to commemorate the historic centennial of the Iditarod Trail. Four-time champion Martin Buser is joined this year on the trail by his 22-year-old son Rohn Buser. Kristy and Anna Berington also departed two positions apart from each other and are the first identical twins to compete in the same Iditarod. Mushers began the race Saturday with a ceremonial, untimed 11-mile run through Anchorage, Alaska\'s largest city. The winner of this year\'s race will take home $50,400 and a new truck, part of an overall prize purse of more than $550,000. The race record was set last year by John Baker, who finished in eight days, 18 hours and 46:39 minutes. Most of the Iditarod competitors are from Alaska, but there are also participants from the Lower 48 states, Canada, Germany and Norway. Seventeen women are racing in this year\'s Iditarod, one of the few high-profile sports events where men and women compete together.