	Rhesus factor testing utilises the genotyping technique to detect the presence of the RhD gene. By checking the existence of the RhD gene in the individual's genome, the presence of rhesus D (RhD) antigens can be inferred. Individuals with a positive RhD status has RhD antigens expressed on the cell membrane of their red blood cells, whereas Rhesus D antigens are absent for individuals with negative RhD status.