Emil Heitz (born 19 October 1892 in Strasbourg, then part of the German Empire - died 8 July 1965 in Lugano, Switzerland) was a German-Swiss botanist and geneticist.
[1] In 1928, Heitz detected differences along chromosomes that correlated with linear arrangement of genes, suggesting the terms euchromatin and heterochromatin for differences detectable by suitable chromosomal stains.
[2][3] His subsequent studies developed what he called cytological genetics, laying the ground for what is now termed cytogenetics.
In November 1933 Heitz was a signatory of the Vow of allegiance of the Professors of the German Universities and High-Schools to Adolf Hitler and the National Socialistic State.
In 1955, Heitz was the first winner of the Schleiden Medal.