Garrigan, D. and M.
F. Hammer (2005) Nucleotide polymorphism in ten human
populations. II. Demographic models. In prep. Garrigan, D., Z.
Mobasher, S. B. Kingan, M. M. Pilkington, J. A. Wilder and M. F. Hammer
(2005) Nucleotide polymorphism in ten human populations. I.
Distribution of variation. Genome
Research:
submitted. Garrigan, D., Z.
Mobasher, S. B. Kingan,
J. A. Wilder, J. D. Wall and M. F. Hammer (2005) Deep haplotype
divergence and long-range linkage disequilibrium at Xp21.1 provide
evidence that humans descend from a structured ancestral population. Genetics: in press. Garrigan, D., Z. Mobasher, T. Severson, J.
A. Wilder and M. F. Hammer (2005) Archaic Asian ancestry on the human X
chromosome. Molecular Biology and
Evolution 22: 189-192. Hammer, M. F., D. Garrigan, E. Wood, J. A.
Wilder, Z. Mobasher, A. Bigham, J. G. Krenz and M. W. Nachman (2004)
Heterogeneous patterns of variation among multiple human X-linked loci:
the possible role of diversity reducing-selection in non-Africans. Genetics 167: 1841-1853 Behar, D. M., M. F. Hammer, D. Garrigan,
R. Villems, B. Bonne-Tamir, M. Richards, D. Gurwitz, D. Rosengarten, M.
Kaplan, S. Della Pergola, L. Quintana-Murci and K. Skorecki (2004)
MtDNA evidence for a bottleneck in the early history of the Ashkenazi
Jewish population. European Journal of
Human Genetics 12: 355-364. Garrigan, D. and P. W. Hedrick (2003)
Perspective: detecting adaptive molecular polymorphism, lessons from
the MHC. Evolution 57:
1707-1722. University of Arizona Tucson, AZ 85721 Phone: (520)
626-1626 Fax:
(520) 626-8050 Email: garrigan@email.arizona.edu
Selected Publications
Research Interests
Ancient
Human Population Structure. We have found evidence that anatomically
modern humans descend from multiple archaic populations in both Africa
and Eurasia. We are currently surveying 90
non-coding regions of the human genome for this signal of ancient
population structure as part of a 5 year NSF HOMINID grant. We are estimating three parameters of a
coalescent model developed by Nordborg, including population divergence
time, admixture time, and proportion of archaic ancestry.
The significance of this work is that it
demonstrates that the ancestors of the anatomically modern human
population were not reproductively isolated and, therefore, did not
meet the criteria for a distinct species.
Multi-Locus
Analysis of Population History. We are interested in creating novel data
analysis methodologies that accommodate multi-locus data.
Such data, especially from different compartments of
the genome with different effective population sizes (i.e.,
mtDNA, Y chromosome, X chromosome, and autosomes), greatly improve the
power to estimate parameters of a population’s demographic history.
Genetics
of Small Populations. The dynamics of genetical evolution in small
populations is highly stochastic. We are
interested in how recessive disease mutations behave in such
populations. Our model is the Ashkenazi
Jewish population. We have shown that this
population derives from a larger ancestral Near Eastern population. Recessive disease mutations are expected to be
maintained at low frequency in a large population due to
mutation-selection balance. Upon the
founding of a new, much smaller population most of these mutations will
be lost. However, those disease mutations
that do survive the founder event are expected to increase in frequency. Thus, there is a period of time after the
founding of a new population that it must be purged of this inherited
genetic load by natural selection.
Dan Garrigan
Research Associate
Genomic Analysis &
Technology Core