Modern blood group testing and genetic testing are based on the theory and technology of biology, genetics and related disciplines, and judge whether there is a biological relationship between the defendant's parents and children according to the genetic law of genetic traits between offspring and parents. Therefore, the method of dropping blood is not reliable.
Anecdotes of acquaintances
In Southern History, Wu Shuyuan, the mother of Xiaozong, is the concubine of Dong Hunhou, beautiful as a fairy and a geisha. She was chosen by Emperor Wu and gave birth to Xiao Zong in seven months. Most people suspect that this is not the credit of Emperor Wu. When Xiaozong grew up, he doubted it himself, so he went to rob Dong Hunhou's tomb, dug up the bones, and dropped his own blood on the bones, and the blood immediately penetrated into the bones.
In order to be prudent and scientific, Xiaozong killed his son again, dripping his blood on his son's bones and infiltrating into them. Filial piety is convinced. He went to another country (Northern Wei Dynasty), changed his name to Xiao Huan, and was declared mourning for three years.
According to Xie Cheng's Biography of the Sages in Huiji, 50 or 60 brothers died across the sea. The body was decomposed and unrecognizable. Kerwin Chen cried and said, "I heard that all relatives are connected", so his bones bled and the blood immediately oozed. Other family members followed suit and found self-righteous relatives, so everyone in the square was crying loudly.