Harding, who was part of the pop group Girls Aloud, died from the disease aged 39 in 2021 and one of her final wishes was to find new ways of spotting breast cancer early when it is more treatable.
The new Breast Cancer Risk Assessment in Younger Women (Bcan-Ray) project will become one of the first in the world to identify which women are at risk of getting the disease in their 30s.
Around 2,300 women aged 39 and under are diagnosed with breast cancer in the UK each year.
The project, which will run in Greater Manchester, is being made possible thanks to funding from the Christie Charity, Cancer Research UK and the Sarah Harding Breast Cancer Appeal, which is supported by Harding's family, friends and Girls Aloud bandmates Cheryl Tweedy, Kimberley Walsh, Nadine Coyle and Nicola Roberts.
Speaking about the study before her death, Miss Harding said: ‘Research is incredibly important in the fight against cancer.
‘Although this research may not be in time to help me, this project is incredibly close to my heart as it may help women like me in the future.'
Miss Harding was treated at the Christie cancer hospital in Manchester.
Catherine Craven-Howe, 33, from Hale in south Manchester, is the first person to take part in the new trial.
She is studying medicine at Liverpool University while working as a healthcare assistant in an eating disorders unit.