Defending champion Serena Williams has been promoted up the Wimbledon seedings from her world ranking of 10 to number one for next week's championships.
Her sister Venus, who triumphed at the All England Club in 2000 and 2001 before finishing runner-up to Serena the following two years, has also been elevated five places from her WTA ranking and named third seed by the organisers this afternoon.
Newly-crowned French Open winner Anastasia Myskina, the highest ranked woman in the draw following the withdrawals of the world's top two players Justine Henin-Hardenne and Kim Clijsters, was seeded second behind Serena.
In the men's event, champion Roger Federer has been made top seed ahead of world number two Andy Roddick.
Unlike every other tournament in the world, Wimbledon does not follow the ATP's world rankings and instead uses a combination of rankings and grasscourt form over recent years when determining men's seeds.
Britain's Tim Henman profited from the system. Four times a semi-finalist at the grasscourt grand slam, he was boosted from his world ranking of six to fifth seed.
Lleyton Hewitt, champion in 2002, was named seventh seed despite being at 10 in the standings while his opponent in that final, Argentina's David Nalbandian was seeded fourth.
Wimbledon runs from June 21st to July 4th.