A brief historical outline of the gradual recognition
of hereditary onycho-osteodysplasia has been given.The investigation of a further family, 3 members of
which exhibit changes characteristic of the nail -patella
syndrome, has been described.Forty -four families exhibiting hereditary onycho- osteodysplasia have been collected from the world literature, the
whole series comprising over 400 affected persons, details
being available, however, for only 252 of these. The manifestationsof the syndrome in the latter group have been
analysed in order to find the relative incidence of the
individual anomalies comprising the syndrome, and of the
different combinations in which they occur. It has been
suggested that the pelvic anomalies occur much more frequently than has previously been believed.An account has also been given of various other abnormalities which have from time to time been reported as occurring in association with the nail -patella syndrome and
an attempt has been made to classify these and determine
their true relationship to the syndrome itself. The present
author's opinion is that, with the exception of a few
associated hereditary anomalies which may possibly exhibit
"linkage" with the main syndrome, the other subsidiary
lesions are almost certainly coincidental.Finally, a brief account has been given of what is known
of the genetic factors involved in the transmission of the
syndrome. Evidence has also been presented that there are strong grounds for believing that the anomaly has arisen as
a spontaneous mutation in the family reported in this article
