nairobi olympic silver medallist christine mboma and her namibian teammate beatrice masilingi who are both unable to compete at certain events due to differences in sexual development dsd qualified comfortably for the 200m final at the world athletics under20s championships on friday while sasha zhoya broke the age group 110m hurdles world recordmasilingi who took silver in thursdays 100m final behind jamaicas tina clayton was the fastest of the finalists as she won her semifinal in a championship record time of 2219secnigerias favour ofili was second quickest in 2237sec with mboma just behind having also broken the championship record in the first semifinal in 2241secboth mboma and masilingi are determined as having differences in sexual development dsd or intersex athletes with naturally high testosterone levelsunder world athletics rules the two sprinters rare physiology is deemed to give them an unfair competitive advantage in track events ranging between 400m and one milezhoya who was born and bred in australia to a zimbabwean father and french mother produced a superb semifinal run to break the under20 world record for the 110m hurdles and then said he had not been happy with his runthere was a lot of mistakes i hit the last four hurdles he said my coach will have a stern wordas he crossed the line i said to myself ah wellbut he still had the recordone of my goals has been achieved i can put a cross next to it the world record is done he saidthe 19yearolds time of 1293sec was marginally quicker than the 1299sec set by another frenchman wilhem belocian in 2014 and equalled three years ago by jamaican damion thomasboth finals are scheduled to take place on saturday