The small village of Chican in Yucatán has less of 1,000 inhabitants, 81% of the population speak the indigenous Mayan language, and almost no dwelling has a computer. Surrounded by dense forests, it is very hard to drive to this small Mexican town which during decades has been trying to keep intact their customs and traditions, but the most dangerous way to try it is the practice of getting married only to individuals of the same Mayan race, with no matter whether they are relatives or not, and whith the high genetic risks of this.
In fact, 75% of the families in Chican have, at least, one member who is deaf-mute. According to this article by ‘El Universal’ and ReporterosHoy, the people of the village are aware of the danger of the procreation between relatives, because researchers of several Universities and the local authorities have been warning them since the decade of the 70’s. For instance, the different studies found that there are only two “nuclear families”, whose members have been getting married among them during a big number of generations, with the result of a genetic modification which produced more deaf-mute descendants.
This genetic modification started to create deaf-mute individuals and of course, their own Sign Language arose, which has been investigating for decades. For instance, the study “Sign Language, Culture & Community in a Traditional Yucatec Maya Village” of 1991 analyzed the “unusually high number of deaf inhabitants” of Chican, finding that their Sign Language was not the same one as that of the deaf inhabitants of the towns and cities of Mexico. There are more studies in this and this link.
Credit of the photo: “Un pueblo incluyente: Chicán“.