Jan Janský


Prof. MUDr. Jan Janský was a Czech serologist, neurologist and psychiatrist. He is credited with the first classification of blood into the four types of the ABO blood group system.
Janský studied medicine at Charles University in Prague. From 1899, he worked in the Psychiatric Clinic in Prague. In 1914, he was named professor. During World War I Janský served two years as a doctor at the front until a heart attack disabled him. After the war he worked as a neuropsychiatrist in a military Hospital. He had angina pectoralis and died of ischaemic heart disease.
Janský was also a proponent of voluntary blood donations.

Classification

Through his psychiatric research, Janský tried to find a correlation between mental diseases and blood diseases. He found no such correlation existed and published a study, Hematologická studie u psychotiků, in which he classified blood into four groups I, II, III, IV. At the time this discovery passed almost unnoticed. In 1921 an American medical commission acknowledged Janský's classification. Janský's classification remains in use today. A similar classification was described by William Lorenzo Moss, except the I and IV of Moss were the opposite to that of Janský's, leading to confusion in blood transfusion until the use of A, B and O became standard.

Legacy