Department of Science, Technology, and Mathematics, Gallaudet University, Washington, D.C., United States of America.
Department of History, Philosophy, Religion, and Sociology, Gallaudet University, Washington, D.C., United States of America.
PLoS One. 2020 Nov 4;15(11):e0241609. doi: 10.1371/journal.pone.0241609. eCollection 2020.
The idea that deaf intermarriage increases the prevalence of deafness was forcefully pushed in the late 19th century by Alexander Graham Bell, in proceedings published by the National Academy of Science. Bell's hypothesis was not supported by a 19th century study by Edward Allen Fay, which was funded by Bell's own organization, the Volta Bureau. The Fay study showed through an analysis of 4,471 deaf marriages that the chances of having deaf children did not increase significantly when both parents were deaf. In light of an apparent increase in non-complementary pairings when a modern dataset of Gallaudet alumni was compared with the 19th century Fay dataset, Bell's argument has been resurrected. This hypothesis is that residential schools for the deaf, which concentrate signing deaf individuals together, have promoted assortative mating, which in turn has increased the prevalence of recessive deafness and also the commonest underlying deafness allele. Because this hypothesis persists, even though it contradicts classical models of assortative mating, it is critically important that it be thoroughly investigated. In this study, we used an established forward-time genetics simulator with parameters and measurements collected from the published literature. Compared to mathematical equations, simulations allowed for more complex modeling, operated without assumptions of parametricity, and captured ending distributions and variances. Our simulation results affirm predictions from classical equations and show that intense assortative mating only modestly increases the prevalence of deafness, with this effect mostly completed by the third generation. More importantly, our data show that even intense assortative mating does not affect the frequency of the underlying alleles under reported conditions. These results are not locus-specific and are generalizable to other forms of recessive deafness. We explain the higher rate of non-complementary pairings measured in the contemporary Gallaudet alumni sample as compared to the Fay dataset.
聋人通婚会增加聋人比例的观点在 19 世纪末期由亚历山大·格雷厄姆·贝尔（Alexander Graham Bell）在国家科学院的会议记录中大力推广。爱德华·艾伦·费伊（Edward Allen Fay）的一项 19 世纪的研究并没有支持贝尔的假设，该研究是由贝尔自己的组织“伏塔局”资助的。费伊的研究通过对 4471 对聋人婚姻的分析表明，当父母双方都是聋人时，生育聋儿的几率并没有显著增加。鉴于在将现代盖尔聋哑人校友数据集与 19 世纪的费伊数据集进行比较时，非互补配对的情况明显增加，贝尔的论点被重新提出。这一假设是，聋人寄宿学校将聋人集中在一起，促进了同型交配，从而导致隐性耳聋和最常见的耳聋等位基因的患病率增加。由于这一假设仍然存在，尽管它与同型交配的经典模型相矛盾，但彻底调查这一假设至关重要。在这项研究中，我们使用了一个经过验证的正向遗传模拟器，该模拟器使用了从已发表的文献中收集的参数和测量值。与数学方程相比，模拟允许更复杂的建模，不需要参数性假设，并且可以捕获结束分布和方差。我们的模拟结果证实了经典方程的预测，并表明强烈的同型交配只会适度增加耳聋的患病率，这种效应主要在第三代完成。更重要的是，我们的数据表明，即使是强烈的同型交配也不会在报告的条件下影响潜在等位基因的频率。这些结果不是特定于基因座的，并且可以推广到其他形式的隐性耳聋。我们解释了与费伊数据集相比，当代盖尔聋哑人校友样本中测量到的非互补配对率较高的原因。
