On the genetic architecture of cortical folding and brain volume in primates.

TitleOn the genetic architecture of cortical folding and brain volume in primates.
Publication TypeJournal Article
Year of Publication2010
AuthorsRogers, J, Kochunov, P, Zilles, K, Shelledy, W, Lancaster, J, Thompson, P, Duggirala, R, Blangero, J, Fox, PT, Glahn, DC
JournalNeuroimage
Volume53
Issue3
Pagination1103-8
Date Published2010 Nov 15
ISSN1095-9572
KeywordsAnimals, Biological Evolution, Cerebral Cortex, Female, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Male, Papio, Primates, Species Specificity
Abstract

Understanding the evolutionary forces that produced the human brain is a central problem in neuroscience and human biology. Comparisons across primate species show that both brain volume and gyrification (the degree of folding in the cerebral cortex) have progressively increased during primate evolution and there is a strong positive correlation between these two traits across primate species. The human brain is exceptional among primates in both total volume and gyrification, and therefore understanding the genetic mechanisms influencing variation in these traits will improve our understanding of a landmark feature of our species. Here we show that individual variation in gyrification is significantly heritable in both humans and an Old World monkey (baboons, Papio hamadryas). Furthermore, contrary to expectations based on the positive phenotypic correlation across species, the genetic correlation between cerebral volume and gyrification within both humans and baboons is estimated as negative. These results suggest that the positive relationship between cerebral volume and cortical folding across species cannot be explained by one set of selective pressures or genetic changes. Our data suggest that one set of selective pressures favored the progressive increase in brain volume documented in the primate fossil record, and that a second independent selective process, possibly related to parturition and neonatal brain size, may have favored brains with progressively greater cortical folding. Without a second separate selective pressure, natural selection favoring increased brain volume would be expected to produce less folded, more lissencephalic brains. These results provide initial evidence for the heritability of gyrification, and possibly a new perspective on the evolutionary mechanisms underlying long-term changes in the nonhuman primate and human brain.

DOI10.1016/j.neuroimage.2010.02.020
Alternate JournalNeuroimage
PubMed ID20176115
PubMed Central IDPMC3137430
Grant ListC06-RR014578 / RR / NCRR NIH HHS / United States
R01 MH078111-01 / MH / NIMH NIH HHS / United States
P51-RR013986 / RR / NCRR NIH HHS / United States
C06-RR015456 / RR / NCRR NIH HHS / United States
K01 EB006395 / EB / NIBIB NIH HHS / United States
R01 MH078111 / MH / NIMH NIH HHS / United States
C06 RR013556 / RR / NCRR NIH HHS / United States
MH078143 / MH / NIMH NIH HHS / United States
R01 MH078143-02 / MH / NIMH NIH HHS / United States
R01 MH059490 / MH / NIMH NIH HHS / United States
R01 MH078143 / MH / NIMH NIH HHS / United States
K01 EB006395-02 / EB / NIBIB NIH HHS / United States
R37 MH059490 / MH / NIMH NIH HHS / United States
P51 RR013986-09 / RR / NCRR NIH HHS / United States
C06 RR014578 / RR / NCRR NIH HHS / United States
P51 RR013986-076712 / RR / NCRR NIH HHS / United States
C06-RR013556 / RR / NCRR NIH HHS / United States
R01 MH083824 / MH / NIMH NIH HHS / United States
R37 MH059490-10 / MH / NIMH NIH HHS / United States
P51 RR013986-085948 / RR / NCRR NIH HHS / United States
MH078111 / MH / NIMH NIH HHS / United States
C06 RR015456 / RR / NCRR NIH HHS / United States
MH059490 / MH / NIMH NIH HHS / United States
P51 RR013986 / RR / NCRR NIH HHS / United States