A Roadmap for Developing and Implementing Duffy Null-Specific Reference Intervals

The Duffy null variant is found in 10% of the United States population, and results in distinct absolute neutrophil counts (ANC) and white blood cell count (WBC) RIs. Investigators from twenty-three institutions completed a collaborative assessment of ANC and WBC in healthy Duffy-null pediatric and adult participants. This report summarizes a roadmap for developing and implementing Duffy-null RIs and infrastructure. Through consensus, we identified the following key themes: 1) Identifying Stakeholders and Funding, 2) Collecting Samples, 3) Testing for Duffy Status, 4) Implementing Duffy-Specific Policies and Tools, and 5) Educating Providers and Duffy-null individuals. Across themes, we outline challenges and opportunities relevant to the development and implementation of Duffy-null infrastructure. We provide examples from community and academic practice settings as well as sites with geographic, size, funding, and population diversity. This roadmap will support healthcare systems, hospitals, and laboratories in developing and implementing Duffy-specific infrastructure.