1866 DOWN, John Langdon Haydon (1828 – 1896)

Observations on an ethnic classification of idiots.

Langdon Down suggested that the physiognomical features of certain defectives enabled them to be arranged in ethnic groups; of these he differentiated Mongolian, Ethiopian, Caucasian, and American Indian. Such an ethn…

GMN 4936 · https://historyofmedicine.com/id/6184

1928 BROUSSEAU, Kate ( – 1938)

Mongolism. A study of the physical and mental characteristics of mongolian imbeciles. Revised by H. G. Brainerd.

Down syndrome.

GMN 4958 · https://historyofmedicine.com/id/6301

1938 PENROSE, Lionel Sharples (1898 – 1972)

A clinical and genetic study of 1,280 cases of mental defect.

In this exhaustive study Penrose showed (p. 36) the significance of maternal age in the etiology of Down syndrome.

GMN 4962.1 · https://historyofmedicine.com/id/6325