Distribution patterns of variability for 18 immune system genes in Amerindians – relationship with history and epidemiology

Abstract

Native American populations generally have a higher prevalence of infectious diseases than non-Native populations and this fact can induce different pressures in their immune system. We investigated the patterns of population differentiation (FST ) of 32 polymorphisms related to adaptive immune response in four Native American populations (Aché, Guarani-Kaiowá, Guarani-Ñandeva and Kaingang), and the results were compared with the three major world population data [Yoruba of Ibadan, Nigeria (YRI), Utah residents with northern and Western Europe ancestry (CEU) and Han Chinese of Beijing, China (CHB)] available in the HapMap database. The Aché clearly differentiated from the other Amerindians, but when all Native Americans were compared with the samples of other ethnic groups the lowest difference (0.08) was found with CHB (Asians), the second lowest (0.15) with YRI (Africans) and the most marked with CEU (European-derived). The considerable intra and interethnic differences found can be explained both in terms of diverse evolutionary distances and more recent environmental pathogen exposures; and they should be appropriately considered prior to any specific public health action.

The correlation between ancestry and color in two cities of Northeast Brazil with contrasting ethnic compositions

“…The CHB population has been shown to have similar allele frequencies to Native Americans. [11][12][13] In addition, 64 individuals from different indigenous tribes in Latin America of the HGDP-CEPH Diversity Panel (NAM) were used as Amerindian reference population with 108 markers common to all data sets. 14 For Structure analyses, the admixture model was employed assuming correlated population allele frequencies with a burn-in period of 10 000 and 100 000 iterations.…”

Variability of innate immune system genes in Native American populations—relationship with history and epidemiology

“…Several investigations reported that Native American populations have a lower variability in several immune system genes such as KM, GM, Kell, HLA, and KIR (Bhatia et al, 1995;Black and Pandey, 1997;Black, 2004;Prugnolle et al, 2005;Augusto et al, 2013Augusto et al, , 2015. Recently it has been reported that the pattern of adaptive immune system variability in Amerindians populations differs from that observed in the HapMap CEU population as evaluated by F ST analyses (Lindenau et al, 2013). It is well established that environmental exposure to parasites, helminths, and physical injuries were very different during the evolutionary histories of world populations, leading to differences in immune response patterns observed among these groups (Finkelman and Urban, 2001;Hurtado et al, 2003;Lazzaro and Little, 2009;Schulenburg et al, 2009;Cagliani and Sironi, 2013).…”

The role of variants from the innate immune system genes in tuberculosis and skin test response in a Native American population

“…Low diversity was observed in South Native American populations for several genetic markers, among them HLA, KIR, and microsatellites [4][5][6]12]. The Aché population was the one with the lowest observed heterozygosity among the Native American populations studied for the above mentioned markers.…”

“…This differential susceptibility is usually explained by the nontraditional variability in the HLA/KIR, adaptive and innate immune systems genes [4][5][6][7]. The reduced variability in the HLA system was associated with higher purified protein derivative skin test response (PPD) reaction in the Aché population [8].…”