Studying genetic mechanisms underlying primate brain morphology can provide insight into the evolution of human brain structure and cognition. In humans, loss‐of‐function mutations in the gene coding for ASPM (Abnormal Spindle Microtubule Assembly) have been associated with primary microcephaly, which is defined by a significantly reduced brain volume, intellectual disability and delayed development. However, less is known about the effects of common
The evolutionarily conserved splicing regulator neuro-oncological ventral antigen 1 (
- NSF-PAR ID:
- 10214346
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- American Association for the Advancement of Science (AAAS)
- Date Published:
- Journal Name:
- Science
- Volume:
- 371
- Issue:
- 6530
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- Article No. eaax2537
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract ASPM variation in humans and other primates. In this study, we characterized the degree of coding variation atASPM in a large sample of chimpanzees (N = 241), and examined potential associations between genotype and various measures of brain morphology. We identified and genotyped five non‐synonymous polymorphisms in exons 3 (V588G), 18 (Q2772K, K2796E, C2811Y) and 27 (I3427V). Using T1‐weighted magnetic resonance imaging of brains, we measured total brain volume, cerebral gray and white matter volume, cerebral ventricular volume, and cortical surface area in the same chimpanzees. We found a potential association betweenASPM V588G genotype and cerebral ventricular volume but not with the other measures. Additionally, we found that chimpanzee, bonobo, and human lineages each independently show a signature of acceleratedASPM protein evolution. Overall, our results suggest the potential effects ofASPM variation on cerebral cortical development, and emphasize the need for further functional studies. These results are the first evidence suggestingASPM variation might play a role in shaping natural variation in brain structure in nonhuman primates. -
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