Volume 12

Treasury of human inheritance / edited by Karl Pearson, R.A. Fisher, L.S. Penrose.

Date:
1909-
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Treasury of human inheritance / edited by Karl Pearson, R.A. Fisher, L.S. Penrose. Source: Wellcome Collection.

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    have commenced late in life may or may not be truly homogeneous with those of our series. The reader who glances at the ages of onset of peroneal atrophy on the pedigree plates appended cannot fail to be struck by the obvious tendency for members of the same sibship to become affected at the same period, often indeed the same year, of life; the correlation coefficient cannot be regarded as an accurate or satisfactory measure of this tendency when many of the affected members of the population concerned are young and may presumably have siblings who could still develop the disease late in life and markedly reduce the value of the correlation; yet some measure of the association is of great practical importance to the members of affected families ; they want to know how far they can rely upon the observations, within their own experience, as a guide to the age at which they may rest assured of freedom from the liability to develop the disease in themselves or their children. Whatever the influence of selection may be on an individual correlation coefficient, it should apply to some extent to all similar material similarly collected, referring to other diseases and it is certainly of interest to compare the values found for peroneal atrophy, hereditary optic atrophy, Huntington’s chorea, and hereditary glaucoma, given in the table below. They suggest that non-affected members of Table 3 All cases Pairs of siblings Correlation coefficient Peroneal atrophy. One parent affected: Mean age of onset (years) Standard deviation ... (220) 18-95 13-59 (164) 23-02 12-22 0-803 Peroneal atrophy. Neither parent affected: Mean age of onset (years) Standard deviation (86) 10-93 9-65 (108) 10-97 10-50 0-840 Hereditary optic atrophy. Males only: Mean age of onset (years) Standard deviation (669) 23-23 9-98 (812) 22-41 9-64 0-510 Huntington’s chorea: Mean age of onset (years) Standard deviation (460) 35-51 12-38 (442) 35-25 10-46 0-465 Hereditary glaucoma: Mean age of onset (years) Standard deviation ... (196) 34-44 17-99 (256) 34-38 17-02 0-897 Peroneal atrophy. One parent affected: Mean age of onset (years) Standard deviation Parent Offspring (220) 18-95 13-59 (86) 24-30 15-05 19-36 11-55 0-764 Huntington’s chorea: Mean age of onset (years) Standard deviation ... (460) 35-51 12-38 (153) 40-80 10-71 31-98 10-57 0-593 Hereditary glaucoma: Mean age of onset (years) Standard deviation (196) 34-44 17-99 (113) 42-08 18-77 30-66 15-12 0-813 Numbers in brackets represent number of oases.