Physiological adaptations to cold stress and the health consequences of the collapse of the Soviet Union on indigenous Siberian populations
Since 1991, we have conducted research on the biology and health of indigenous populations of Siberia -- the Evenki, Kets, Buryat and Yakut. This work has been conducted in collaboration with colleagues from the Russian Academy of Sciences (Victor Spitsyn, Ludmilla Osipova, and Rem Sukernik) and the University of Kansas (Michael H. Crawford). We have examined 1) how indigenous Siberians have physiologically and genetically adapted to the extreme conditions of their environment; and 2) how previous and ongoing social and economic changes in Russia are affecting the health and demographic structure of these populations.
Energetics and Metabolic Adaptation
Previous research on northern populations such as the Eskimo/Inuit has suggested that these groups display increased metabolic rates, perhaps reflecting an adaptation to the extreme cold of their arctic environments. Our work among indigenous Siberians has shown that these groups show elevated resting metabolism as well as high levels of energy expenditure associated with subsistence activities. Moreover, it appears that these elevated resting metabolic rates may have a genetic component, since indigenous Siberians have higher metabolic rates than non-indigenous Russians living in the same communities. Our work further indicates that these distinctive metabolic profiles are a product of alterations in thyroid hormone metabolism.
Social & Economic Influences on Health
The second component of our Siberian work has explored how socioeconomic and political changes in Russia have influenced the lifestyle and health of indigenous Siberians. Unlike indigenous northern populations of Alaska and Canada, the native Siberian groups that we have studied show relatively low levels of obesity and other chronic disease risk factors such as elevated cholesterol and high blood pressure. These lower rates of chronic diseases reflect the fact that most indigenous Siberians continue to live a more traditional lifestyle than native North American groups. Consequently, the high activity levels of their traditional lifestyle contribute to higher levels of fitness and lower levels of obesity in the Siberians. Ongoing changes and the erosion of traditional lifeways, however, do appear to be increasing chronic disease risk among Siberians. This is particularly true among women who have much lower activity levels than men, and show much higher rates of obesity and cardiovascular disease mortality.
Social and economic changes since the fall of Communism have had a profound effect on the health of indigenous children. Since the collapse of the Soviet Union, indigenous communities of Siberia have become increasingly isolated due to reduced governmental support and the high cost of helicopter transport into the region. These changes have resulted in more restricted access to medical care and non-local foods, and appear to be compromising the nutritional health of young children. Between 1991 and 1995, the number of young Evenki children under 6 years of age showing severe growth retardation (e.g., low height or low weight-for-age) more than doubled. We are continuing to explore how the ongoing social and economic changes in Russia are influencing the health of these Siberian groups.
Leonard, W.R. and M.H. Crawford, Eds. (2002). Human Biology of Pastoral Populations. Cambridge University Press, February 2002.
Papers & Book Chapters
Crawford, MH, WR Leonard and RI Sukernik (1992) Biological diversity and ecology in the Evenki of Siberia. MAB Northern Sciences Network Newsletter 1:13-14.
Leonard, WR, MH Crawford, AG Comuzzie, and RI Sukernik (1992) New light on nutrition and peopling of the New World. Arctic Research of the US 6:13-16.
Novoradovsky, AG, VA Spitsin, R Duggirala and MH Crawford (1993) Population genetics and structure of Buryats from Lake Baikal region. Human Biology 65: 689-710.
Torroni, A, RI Sukernik, TG Schurr, YB Starikovskaya, MF Cabell, MH Crawford, AG Comuzzie, and DC Wallace (1993) Mitochondrial DNA variation of aboriginal Siberians reveals distinct genetic affinities with native Americans. American Journal of Human Genetics 53:563-590.
Crawford, MH, AG Comuzzie, WR Leonard, and RI Sukernik (1994) Molecular genetics, protein variation and the population structure of the Evenki: In: CL Markert, JG Scandalios, HA Lim and O Serov (eds.), Isozymes: Organization and roles in evolution, genetics and physiology. World Scientist: NJ, pp. 227-241.
Katzmarzyk PT, WR Leonard, MH Crawford and RI Sukernik (1994) Resting metabolic rate and daily energy expenditure among two indigenous Siberian populations. American Journal of Human Biology 6:719-730.
Katzmarzyk PT, WR Leonard, MH Crawford and RI Sukernik (1994) Predicted maximal oxygen consumption of indigenous Siberians. American Journal of Human Biology 6:783-790.
Leonard WR and PT Katzmarzyk (1994) Nutritional ecology and energetics of the Evenki herders of Central Siberia. In: A Herring and L Chan (eds.): Strength in Diversity: A Reader in Physical Anthropology. Canadian Scholars' Press: Toronto, pp. 303-326.
Leonard WR, MH Crawford, AG Comuzzie and RI Sukernik (1994) Correlates of low serum lipid levels among the Evenki herders of Siberia. American Journal of Human Biology 6:329-338.
Leonard WR, PT Katzmarzyk, AG Comuzzie, MH Crawford, and RI Sukernik (1994) Growth and nutritional status of the Evenki reindeer herders of Siberia. American Journal of Human Biology 6:339-350.
Lin SJ, K Tanaka, W Leonard, T Gerelsaikhan, B Dashnyam, S Nyamkhishig, A Hida, Y Nakahori, K Omoto, MH Crawford, and Y Nakagome (1994) A Y-associated allele is shared among a few ethnic groups of Asia. Japanese Journal of Human Genetics 39:299-304.
Comuzzie AG, R Duggirala, WR Leonard, and MH Crawford (1995) Population relationships among historic and modern indigenous populations. Human Biology 67:459-479.
McComb J, N Blagitko, AG Comuzzie, MS Shanfield, RI Sukernik, WR Leonard, and MH Crawford (1995) VNTR population variation in Siberian indigenous populations. Human Biology 67:217-229.
Kamboh MI, MH Crawford, CE Aston, and WR Leonard (1996) Population distributions of APOE, APOH and APOA4 polymorphisms and their relationships with quantitative plasma lipid levels among the Evenki herders of Siberia. Human Biology 68:231-243.
Katzmarzyk PT, WR Leonard, MA Stephen, PR Berti and AGP Ross (1996) Differences between observed and predicted energy costs at rest and during exercise in three indigenous populations. American Journal of Physical Anthropology 99:537-545.
Leonard WR, PT Katzmarzyk, and MH Crawford (1996) Energetics and population ecology of Siberian herders. American Journal of Human Biology 8:275-289.
McComb J, MH Crawford, L Osipova, T Karaphen, O Posukh, and MS Shanfield (1996) DNA inter-populational variation in Siberian Indigenous populations. American Journal of Human Biology 8:599-607.
McComb J, MH Crawford, WR Leonard, MS Shanfield and L Osipova (1996) Applications of DNA fingerprints in the study of genetic structure in human populations. In: 21st Symposium in honor of Stadler, Eds. J.P. Gustafson and R.B. Flavell, Plenum Press: New York, pp. 31-46.
Leonard WR, A Keenleyside, and E Ivakine (1997) Recent fertily and mortality trends among indigenous and non-indigenous populations of Central Siberia. Human Biology 69:403-417.
Leonard WR, VA Galloway and E Ivakine (1997) Underestimation of daily energy expenditure with the factorial method: Implications for anthropological research. American Journal of Physical Anthropology 103:443-454.
Leonard WR, VA Galloway, E Ivakine, L Osipova, and M Kazakovtseva (1999) Nutrition, thyroid function and basal metabolism of the Evenki of Central Siberia. International Journal of Circumpolar Health 58:281-295.
Santos FR, A Pandya, C Tyler-Smith, SD Pena, M Shanfield, WR Leonard, L Osipova, MH Crawford, and RJ Mitchell (1999) The central Siberian origin for native American Y-chromosomes. American Journal of Human Genetics 64:619-628.
Galloway VA, WR Leonard, and E Ivakine (2000) Basal metabolic adaptation of the Evenki reindeer herders of Central Siberia. American Journal of Human Biology 12:75-87.
Mitchell RJ, S Howlett, L Earl, NG White, J McComb, MS Shanfield, I Briceno, SS Papiha, L Osipova, G Livshits, WR Leonard, and MH Crawford. (2000) Distribution of the 3' VNTR polymorphism in the human dopamine transporter gene in world populations. Human Biology 72:295-304.
Crawford MH and WR Leonard (2002) The biological diversity of herding populations. In: WR Leonard & MH Crawford (Eds.): Human Biology of Pastoral Populations.
Cambridge: Cambridge University Press, pp. 1-9.
Crawford MH, J McComb, MS Shanfield, and RJ Mitchell (2002) Genetic structure of pastoral populations of Siberia: the Evenki of central Siberia and the Kizhi of Gorno
Altai. In: WR Leonard & MH Crawford (Eds.): Human Biology of Pastoral Populations. Cambridge: Cambridge University Press, pp. 10-49.
Leonard WR, VA Galloway, E Ivakine, L Osipova, and M Kazakovtseva. (2002) Ecology, health and lifestyle change among the Evenki herders of Siberia. In: WR Leonard & MH Crawford (Eds.): Human Biology of Pastoral Populations. Cambridge: Cambridge University Press, pp. 206-235.
Dissertations and Theses
Comuzzie AG (1993) Genomic, genetic and morphological variation in a sample of modern Evenki, and their relationship to other indigenous Siberian populations. PhD Dissertation, University of Kansas.
Katzmarzyk PT (1993) The adaptive significance of energy expenditure among indigenous Siberian populations. MSc Thesis, University of Guelph.
McComb J (1996) The effect of unique historic and prehistoric events on the gene pool of the Altai-Kizhi: A study of five variable number tandem repeat (VNTR) loci. MA Thesis, University of Kansas.
Galloway VA (1996) Basal metabolic adaptation of the Evenki of Siberia. MSc Thesis, University of Guelph.
Spencer GJ (1998) Changing patterns of growth and development among the Evenki reindeer herders of Central Siberia. MSc Thesis, University of Guelph.