New Chitotriosidase Paper Accepted by Carbohydrate Polymers
Our manuscript entitled “High prevalence of chitotriosidase deficiency in Peruvian Amerindians exposed to chitin-bearing food and enteroparasites” has been accepted for publication in the Elsevier Journal Carbohydrate Polymers.
The work describes CHIT1 genotype frequencies in a South American indigenous population with very low genetic admixture and very high exposure to chitin, through parasites and food, reflecting an ancestral lifestyle. In the Peruvian Andes and Amazons a high ethnic diversity is still preserved. Amerindians live in small communities of fifty up to several hundred people, and still maintain their original languages and bio-cultural adaptation to specific environmental conditions. Until the 1970s, most Amazonian communities of Peru were geographically isolated as they were cut off from the main routes of transportation, showing the highest prevalence of parasites and the lowest levels of water sanitation and national health-care of the country. Ethnic Amerindians involved in this study belong to five ethnic groups:
- Awajún of Rio Marañon; linguistic family: Jìbaro;
- Ashaninka of Rio Pichis and Perené; linguistic family: Arawaks;
- Shipibo-Conibo of Rio Ucayali (Ucayali Region), recently (2000-2002 a.D.) migrated to Lima; linguistic family: Pano;
- Quechua-Lamas, NC: Lamas, with an Andean ancestry, now living in the high Amazon (San Martìn Region); linguistic family: Quechua;
- Quechua-Cusco, living in Andean highlands (altitude: 3,000-4,000 meters above sea level); linguistic family: Quechua.
Similarly to what we have previously shown for a population in Papua New Guinea, the high frequency of a mutation which makes CHIT1 enzymatically inactive does not seem to support the previously suggested protective roles of this chitinase against malaria and helminth infections.
Considering that the first inhabitants of the New World are thought to have descended from eastern Asian populations between 6 and 30 thousand years ago, it is plausible to assume that the high frequencies of the CHIT1 mutation called H-Allele (> 40%) result from a founder effect in Amerindians.
The work is the fruit of the collaboration between Geneticists and Ethnobiologists from the University of Padova (Prof Maurizio Guido Paoletti and Nicola Manno), colleagues from the University of Trujillo in Peru and our own lab in Nottingham. Much of the work described in this paper was performed by our MSc student Sam Sherratt in 4 short but intense months of experimental work.