Limits...
Low levels of genetic divergence across geographically and linguistically diverse populations from India.

Rosenberg NA, Mahajan S, Gonzalez-Quevedo C, Blum MG, Nino-Rosales L, Ninis V, Das P, Hegde M, Molinari L, Zapata G, Weber JL, Belmont JW, Patel PI - PLoS Genet. (2006)

Bottom Line: We find that populations from India, and populations from South Asia more generally, constitute one of the major human subgroups with increased similarity of genetic ancestry.However, only a relatively small amount of genetic differentiation exists among the Indian populations.Although caution is warranted due to the fact that United States-sampled Indian populations do not represent a random sample from India, these results suggest that the frequencies of many genetic variants are distinctive in India compared to other parts of the world and that the effects of population heterogeneity on the production of false positives in association studies may be smaller in Indians (and particularly in Indian-Americans) than might be expected for such a geographically and linguistically diverse subset of the human population.

View Article: PubMed Central - PubMed

Affiliation: Department of Human Genetics, Bioinformatics Program, and the Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, United States of America. rnoah@umich.edu

ABSTRACT
Ongoing modernization in India has elevated the prevalence of many complex genetic diseases associated with a western lifestyle and diet to near-epidemic proportions. However, although India comprises more than one sixth of the world's human population, it has largely been omitted from genomic surveys that provide the backdrop for association studies of genetic disease. Here, by genotyping India-born individuals sampled in the United States, we carry out an extensive study of Indian genetic variation. We analyze 1,200 genome-wide polymorphisms in 432 individuals from 15 Indian populations. We find that populations from India, and populations from South Asia more generally, constitute one of the major human subgroups with increased similarity of genetic ancestry. However, only a relatively small amount of genetic differentiation exists among the Indian populations. Although caution is warranted due to the fact that United States-sampled Indian populations do not represent a random sample from India, these results suggest that the frequencies of many genetic variants are distinctive in India compared to other parts of the world and that the effects of population heterogeneity on the production of false positives in association studies may be smaller in Indians (and particularly in Indian-Americans) than might be expected for such a geographically and linguistically diverse subset of the human population.

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Mean Fst Values for Each Indian Group across Comparisons with 18 Populations from East Asia, 12 Populations from Europe and the Middle East, and the Other 14 Groups from India(A) 715 microsatellites.(B) 207 indels.Error bars denote standard deviations across comparisons.
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pgen-0020215-g005: Mean Fst Values for Each Indian Group across Comparisons with 18 Populations from East Asia, 12 Populations from Europe and the Middle East, and the Other 14 Groups from India(A) 715 microsatellites.(B) 207 indels.Error bars denote standard deviations across comparisons.

Mentions: Figure 5 illustrates both the relatively low levels of genetic differentiation among populations within India and the comparatively higher levels of divergence between Indian populations and those of Europe and the Middle East, as well as with those of East Asia. Consistent with geography and with the analysis in Figure 2A, among the Indian populations, populations from the northwest part of India, including the Kashmiri and Punjabi groups, had the greatest similarity to the populations from Europe and the Middle East. Populations from eastern India, including the Assamese and Bengalis, had the greatest similarity to the populations from East Asia. The only population whose Fst values within India substantially overlapped those of either Europe/Middle East or East Asia was the Parsi population. Fst values for the Parsis were similar within India and with populations from Europe and the Middle East, in agreement with their likely origins and their similar membership in the blue and red clusters in Figure 2A (52.4% for the blue cluster, 45.3% for the red cluster). In general, Fst between pairs of populations within India did not show a strong correlation with geographic distance (Figure 6). The correlation was greater when excluding pairs involving the Parsi population, but remained considerably smaller than has been seen for other sets of worldwide populations [20,21].


Low levels of genetic divergence across geographically and linguistically diverse populations from India.

Rosenberg NA, Mahajan S, Gonzalez-Quevedo C, Blum MG, Nino-Rosales L, Ninis V, Das P, Hegde M, Molinari L, Zapata G, Weber JL, Belmont JW, Patel PI - PLoS Genet. (2006)

Mean Fst Values for Each Indian Group across Comparisons with 18 Populations from East Asia, 12 Populations from Europe and the Middle East, and the Other 14 Groups from India(A) 715 microsatellites.(B) 207 indels.Error bars denote standard deviations across comparisons.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC1713257&req=5

pgen-0020215-g005: Mean Fst Values for Each Indian Group across Comparisons with 18 Populations from East Asia, 12 Populations from Europe and the Middle East, and the Other 14 Groups from India(A) 715 microsatellites.(B) 207 indels.Error bars denote standard deviations across comparisons.
Mentions: Figure 5 illustrates both the relatively low levels of genetic differentiation among populations within India and the comparatively higher levels of divergence between Indian populations and those of Europe and the Middle East, as well as with those of East Asia. Consistent with geography and with the analysis in Figure 2A, among the Indian populations, populations from the northwest part of India, including the Kashmiri and Punjabi groups, had the greatest similarity to the populations from Europe and the Middle East. Populations from eastern India, including the Assamese and Bengalis, had the greatest similarity to the populations from East Asia. The only population whose Fst values within India substantially overlapped those of either Europe/Middle East or East Asia was the Parsi population. Fst values for the Parsis were similar within India and with populations from Europe and the Middle East, in agreement with their likely origins and their similar membership in the blue and red clusters in Figure 2A (52.4% for the blue cluster, 45.3% for the red cluster). In general, Fst between pairs of populations within India did not show a strong correlation with geographic distance (Figure 6). The correlation was greater when excluding pairs involving the Parsi population, but remained considerably smaller than has been seen for other sets of worldwide populations [20,21].

Bottom Line: We find that populations from India, and populations from South Asia more generally, constitute one of the major human subgroups with increased similarity of genetic ancestry.However, only a relatively small amount of genetic differentiation exists among the Indian populations.Although caution is warranted due to the fact that United States-sampled Indian populations do not represent a random sample from India, these results suggest that the frequencies of many genetic variants are distinctive in India compared to other parts of the world and that the effects of population heterogeneity on the production of false positives in association studies may be smaller in Indians (and particularly in Indian-Americans) than might be expected for such a geographically and linguistically diverse subset of the human population.

View Article: PubMed Central - PubMed

Affiliation: Department of Human Genetics, Bioinformatics Program, and the Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, United States of America. rnoah@umich.edu

ABSTRACT
Ongoing modernization in India has elevated the prevalence of many complex genetic diseases associated with a western lifestyle and diet to near-epidemic proportions. However, although India comprises more than one sixth of the world's human population, it has largely been omitted from genomic surveys that provide the backdrop for association studies of genetic disease. Here, by genotyping India-born individuals sampled in the United States, we carry out an extensive study of Indian genetic variation. We analyze 1,200 genome-wide polymorphisms in 432 individuals from 15 Indian populations. We find that populations from India, and populations from South Asia more generally, constitute one of the major human subgroups with increased similarity of genetic ancestry. However, only a relatively small amount of genetic differentiation exists among the Indian populations. Although caution is warranted due to the fact that United States-sampled Indian populations do not represent a random sample from India, these results suggest that the frequencies of many genetic variants are distinctive in India compared to other parts of the world and that the effects of population heterogeneity on the production of false positives in association studies may be smaller in Indians (and particularly in Indian-Americans) than might be expected for such a geographically and linguistically diverse subset of the human population.

Show MeSH
Related in: MedlinePlus