Taipei Veterans General Hospital (VGH) blood bank medical test technologist Liu Hsueh-mei points out that O-type blood contains both A and B type antigens, while B type blood contains both O and A type antigens. Dripping different types of blood into water will cause them to coalesce accordingly. But other than this, it is difficult to glean any further conclusions about the two people.
以第二種「滴血認親」為例，台北榮總血庫醫檢師劉學梅指出，O 型血中有 A 型和 B 型的抗體，反之，B 型血液則有 O、A 型的抗體；將不同血型的血液滴入水中，會產生彼此捉對廝殺的「凝集現象」，除此之外，難以做任何進一步的判定。