A first study of the statistics of pulmonary tuberculosis / by Karl Pearson.
- Karl Pearson
- Date:
- 1907
Licence: In copyright
Credit: A first study of the statistics of pulmonary tuberculosis / by Karl Pearson. Source: Wellcome Collection.
Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.
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![It is not a dogmatic step from this result to assert that the tubercular diathesis is inherited at the same rate as I have found physical characters in man are inherited, namely, somewhere about 46 to ‘50. What we need to supplement the present investigation are more extensive records for the “ completed ” family history of tuberculous stocks. We may note here an interesting point: if we take the 50 per cent, of tuberculous offspring demanded by the Mendelian theory in the case of tuberculous parentage,* we can hardly reach a correlation less than 5. Such a value is inconsistent with the one-third which a simple Mendelian theory demands. This fact coupled with the number of non-tuberculous offspring found in cases where both parents are tuberculous leads me to believe that if pulmonary tubercu- losis has a Mendelian inheritance, the principle of dominance does not apply or applies only—to use a Mendelian phrase—“ with a complication ”. The main result of this investigation is not, however, a question of one or other theory being applicable ; it is the all-important genetic fact that the diathesis of pulmonary tuberculosis is undoubtedly inherited and that the intensity of this inheritance is comparable with that found for normal physical characters in man. A theory of infection does not account for the facts, and there is an anti-social disre- gard for national eugenics in the conduct of medical men who can write to the public press that the marriage or even intermarriage of members of tuberculous stocks is of no social detriment, provided they live with a good supply of fresh air. I am in- clined to think that the risks run, especially under urban conditions, are for tuber- culosis as for a number of other infectious diseases so great, that the constitution or diathesis means almost everything for the individual whose life cannot be spent in self-protection. TABLE OF PARENTAL INHERITANCE. Condition. Source of Statistics. Computer and Locus. Minimum Value. Maximum Value. Probable Value. Pul. Tuberculosis Crossley Sanatorium K. Pearson, this Memoir •40 •60 •50 Insane Diathesis Dr. 0. Diem’s Data /K. Pearson, British Mecl.\ ^ Journ., 1905, p. 1176 J •30 f ? — Hereditary Deaf- ness j-Dr. Fay’s Data fE. Schuster, Biometrika,\ \ vol. iv., p. 466 J ■45 •62 •54 Insane Diathesis Dr. Urquhart’s Data j D. Heron \ l Unpublished results J ? •65 — Character. Stature Span ] Pearson, Family j Records fLee and Pearson, Bio-'\ -j metrika, vol. ii., p. j* l 378 j •49 •45 •51 •46 •51 •46 Forearm ■41 •42 •42 Eye Colour i Galton, Family | Records 1 Lee and Pearson, Phil. f ’I Trans., 195 A, p. 106 j •44 •55 •50 * Really slightly greater as a few cases of both parents tuberculous actually do occur, f This should be really compared with the ’33 aud '44 of this memoir as being based on “ incomplete ” family histories.](https://iiif.wellcomecollection.org/image/b22419081_0019.jp2/full/800%2C/0/default.jpg)
