P528: Detection of non-deletional variants in HBA1 and HBA2 genes through reproductive carrier screening and breakdown by gene, variant, and ethnicity oleh Emily Becraft, Elizabeth Repass, Chris Villalta, Amitha Sandur, Thu-Ha Nguyen, Emily Onyema, Yang Wang, Xingwu Lu, Priyanka Arya, Matthew Prego, Wenbo Xu, Youbao Sha