Director of Rugby Mike Ruddock said: "We are delighted that they have been chosen to represent their country in such prestigious tournaments and wish them all every success."
England coach Ryan added: "Our youth and development is provided by the bulk of the squad notably five of the current U20 squad. Our average age is under 22 and these are the next generation that will benefit hugely by playing in such a massive event.
"For me sevens is part of our overall strategy to get the best out of our young players and together with age group excellence, Premiership academies and the Saxons, sevens is often part of that package to accelerate and achieve more England players ready to step into regular premiership action and beyond.
"Hong Kong is an awesome event. I know I have a side that will crawl off the field for England. This group will give their all for the cause and although we go into this tournament as huge underdogs everyone here is determined to do the white shirt and the red rose justice."
England Sevens squad for IRB World Sevens Series - Hong Kong and Adelaide:
Kevin Barrett (Exeter); John Brake (Northampton Saints); Noah Cato (Saracens); James Collins (Worcester Warriors); Matthew Cox (Worcester Warriors)*; Anthony Elliott (Bristol Rugby); Jonathan Fisher (London Irish)*; Ben Gollings (Sunnybank); Simon Hunt (Ebbw Vale); Chris Mayor (Sale Sharks); Andy Vilk (Sale Sharks, captain); Ben Youngs (Leicester Tigers)*
*denotes uncapped for England Sevens
Cathay Pacific/Credit Suisse Hong Kong Sevens Pool fixtures:
March 28 - England v Canada, KO 8:38pm (local time, GMT+8)
March 29 - England v Sri Lanka, KO 11:58am (local time, GMT+8)
March 29 - Samoa v England, KO 6:34pm (local time, GMT+8)
Adelaide Sevens Pool fixtures:
April 5 - Fiji v England, KO 11:09am (local time, GMT+9.5)
April 5 - England v Kenya, KO 2:37pm (local time, GMT+9.5)
April 5 - England v France, KO 5:21pm (local time, GMT+9.5)