Linkage Disequilibrium

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A study published in 1996 (1) examined The association of genes and/or markers that lie near each other on a chromosome that tend to be inherited together.linkage disequilibrium at the human CD4 The place on a chromosome where a specific gene is located, a kind of address for the gene.locus (a T-cell associated antigen) as a means to establish the date of modern human origins. This study determined a maximum origin date of 102,000 years ago based upon the assumption that the Alu (-) Variant forms of a gene at a particular locus, or location, on a chromosome.alleles arose 5 million years ago, or almost immediately after mankind's split from other An order of mammals including man, apes, monkeys, etc., often characterized by large brains and flexible hands and feet.primates. As they stated, "It is likely that the Alu deletion event occurred more recently, in which case our estimates for the date of founding of the non-African populations would also be more recent." Preliminary studies from Threadlike "packages" of genes and other DNA in the nucleus of a cell. Different kinds of organisms have different numbers of chromosomes. Humans have 23 pairs of chromosomes, 46 in all: 44 autosomes and two sex chromosomes. Each parent contributes one chromosome to each pair, so children get half of their chromosomes from their mothers and half from their fathers.chromosomes 19, 11 and 8 show similar results to that seen on One of the threadlike "packages" of genes and other DNA in the nucleus of a cell. Different kinds of organisms have different numbers of chromosomes. Humans have 23 pairs of chromosomes, 46 in all: 44 autosomes and two sex chromosomes. Each parent contributes one chromosome to each pair, so children get half of their chromosomes from their mothers and half from their fathers.chromosome 12 (the The place on a chromosome where a specific gene is located, a kind of address for the gene.locus of the CD4 gene) (2).

References

1. Tishkoff, S.A., E. Dietzsch, W. Speed, A.J. Pakstis, J.R. Kidd, K. Cheung, B. Bonn-Tamir, A.S. Santachiara-Benerecetti, P. Moral, M. Krings, S. Paabo, E. Watson, N. Risch, T. Jenkins, and K.K. Kidd. 1996. Global patterns of The association of genes and/or markers that lie near each other on a chromosome that tend to be inherited together.linkage disequilibrium at the CD4 The place on a chromosome where a specific gene is located, a kind of address for the gene.locus and modern human origins. Science 271: 1380-1387.

2. Fischman, J. 1996. Evidence mounts for our African origins - and alternatives. Science 271: 1364.