Could endogamy explain the higher prevalence of disabilities in the population of the Brazilian Northeast?

Abstract

Despite conceptual inaccuracies and methods of measurement, the WHO estimates that about 10% of the world population has some form of disability. In order to investigate the prevalence and etiology of disabilities and to evaluate if they could be associated with inbreeding, a cross-sectional epidemiological study was conducted using the informant method in five communities of the state Rio Grande do Norte in the Brazilian Northeast, in which consanguineous marriages frequencies varied between 9 and 32%. The average prevalence of disabilities in the five sampled communities was 4.53%, obtained by interviews that involved 37.87% of a population of 39,054 inhabitants. On average, 25% of consanguineous and 12% of non-consanguineous couples had one or more children with disabilities. The increased rate of individuals with disabilities in the Brazilian Northeast could be associated with the maintenance of the tradition of consanguineous marriages in these populations and some of these disabilities may be caused by genetic disorders.