The intermarriage of relatives and its consequences.

  • C. J. M.
Date:
[1890?]
Catalogue details

Licence: Public Domain Mark

Credit: The intermarriage of relatives and its consequences. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

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    as unfavourable. Of these 883 consanguineous marriages the number of offspring was 3,942 ; 1,134 of them were de- fective in one way or another; 145 were deaf and dumb; 85 were blind; 308 were idiotic; 38 were insane; 60 were epileptic; 300 were scrofulous; 98 were deformed; and 883 died young ... I am satisfied that over 10 per cent, of the deaf and dumb, and over 5 per cent, of the blind, and near 15 per cent, of the idiotic . . . throughout the country at large, are the offspring of kindred parents At the Third Conference of Principals of American Insti- tutions for the Deaf, Dr. Gillett, “ gave it as his belief that from 15 to 25 per cent, of all the blindness, deafness, and idiocy in the world is the result of consanguineous marriages.” I have been courteously favoured by Rev. Brother Stephens, Superior of St. Joseph’s institution at Cabra, Dublin, with the following valuable table, compiled from the Official Query Sheets of Admission, and verified by himself:— — Admitted within last 10 years Of First Cousins Of Second Cousins Of Third Cousins of remote Cousins Degree of relation- ship not given Males - 355 3 8 7 b 4 lc Females 311 0 15a 66 6 lc a. Two of these were members of families containing 4 deaf mutes each. b. These include 1 boy and 1 girl of a family containing 5 deaf mutes each. c. A brother and sister of a family containing 8 deaf mutes each. From the foregoing Table it will appear that of the 666 | children admitted to the Male and Female Institutions at | Cabra, during the decade just ended, 50 were the offspring i of cousin marriages, giving the ratio of 1 to 13’32. But, if to these we add the 15 members of the same families, referred to in the “ notes,” the ratio will stand as 1 to 10'5. 1°. Manifestly, if cousin and non-cousin marriages were in the ratio of 1 to 10, no argument could be formed on the above statistics. But the proportion is enormously less. ,