Her identical twin sister Yasemin (German: Jasmin) is also a swimmer. The twins were born to German father Peter Rosenberger and Turkish mother Leyla Aktaş-Rosenberger, a painter, ceramic artist and sculptor, in Traunstein, Germany.[3] They have a younger sister Deniz, who is also a swimmer. Iris studied business administration at the Ludwig Maximilian University of Munich.[4][5][6][7]
Representing Turkey, Iris took part in the 100 m butterfly event at the 2008 Summer Olympics, where she swam 1:01.67 without advancing to the finals.[8]
In 2009, Iris set new Turkish national records in 50 m butterfly with 27.00 and in 100 m butterfly with 59:45.[9] She holds more than 19 national records for Turkey.[7]