MAJOR HISTOCOMPATIBILITY COMPLEX CLASS-II ALLELES AND HAPLOTYPES AND BLOOD-GROUPS OF 4 AMERINDIAN TRIBES OF NORTHERN COLOMBIA

MHC class II alleles and haplotypes were determined from unrelated ind ividuals and families of the Arhuaco (n = 107), Kogi (n = 42), Arsario (n = 18), and Wayu (n = 88) tribes located in the northern part of Co lombia. Class II DRB, DQA1, and DQB1 alleles were determined by PCR-SS O and PCR-RFLP based methods. Four haplotypes, [DRB1()0407, DRB4(*)01 01, DQA1()03, DQB1(*)03021; DRB1(*)0403, DRB4(*)0101, DQA1(*)03, DQB1 ()0302]; [DRB1(*)1402/1406, DRB3(*)0101, DQA1(*)0501, DQB1(*)0301]; a nd [DRB1()0802, DQA1(*)0401, DQB1(*)0402], were observed among these four tribes. In addition to these haplotypes, the Wayu Indians showed a frequency of 21.3% for the [DRB1()1602, DRB5(*)02, DQA1(*)0501, DQB 1()030] haplotype, 13.1% for the [DRB1(*)0411, DRB4(*)0101, DQA1(*)03 , DQB1()0302] haplotype, and rio showed no genetic admixture while th e Arhuaco tribe showed admixture with genes of African origin and the Wayu showed admixture with Caucasians as well as genes of African orig in. These findings were confirmed by the MHC class II allele and haplo type data obtained, as alleles and haplotypes of Caucasian and African origin were detected in the Wayu and Arhuaco and not in the Kogi or A rsario. These studies will be important in disease association and tra nsplantation studies for Amerindian and Colombian populations and for correlating genetic traits with the anthropologic and linguistic data available in order to better understand the Amerindian populations.