Pheromones, epigenetic imprinting and brain morphology

In 1996 our review article detailed epigenetic effects of pheromones in the context of genomic imprinting effects. Here’s the latest news.

Genomic Imprinting Effects of the X Chromosome on Brain Morphology
J. Neurosci. 2013;33 8567-8574J ean-Francois Lepage, David S. Hong, Paul K. Mazaika, Mira Raman, Kristen Sheau, et al.

X-Chromosome Imprinting Affects Brain Morphology

Epigenetic modification of specific genes in eggs or sperm (genomic imprinting) prevents expression of maternal or paternal alleles in offspring. Imprinting of X-chromosome genes has sex-specific effects, because only females are affected by imprinting on paternally inherited X chromosomes (Xp) and imprinting on maternally inherited X chromosomes (Xm) only affects half of female cells, because one X chromosome is inactivated in each cell. Whether imprinting of X-linked genes contributes to sexual dimorphism in brain anatomy and cognition is unclear. To address this question, Lepage et al. examined girls with Turner syndrome, in which either Xp or Xm and X inactivation are absent. Differences in cortical thickness, surface area, and volume were found in several regions. For example, cortical thickness in temporal areas was greater in Xp than in Xm girls, whereas gray matter volume in superior frontal regions was greater in Xm than in Xp girls. The results suggest that imprinting of X-chromosome genes can influence sexual dimorphism in the brain.

Article excerpt: The present findings have direct implications for our understanding of the epigenetic mechanisms involved in sexual dimorphism of the brain that are taking place early in development.

My comment: 16+ years post publication of our review, and some people are just now starting to catch on. Epigenetic imprinting is not limited to certain species, and epigenetic effects of nutrients and pheromones control species diversity. Clearly, not only can imprinting of X-chromosome genes in mammals influence sexual dimorphism in the brain, it will influence nutrient-dependent pheromone-controlled adaptive evolution of the brain and behavior as it influences genetically predisposed, epigenetically-effected human embodied cognition. How could it not?

Excerpted from our review: From Fertilization to Adult Sexual Behavior (1996)

“Yet another kind of epigenetic imprinting occurs in species as diverse as yeast, Drosophila, mice, and humans and is based upon small DNA-binding proteins called “chromo domain” proteins, e.g., polycomb. These proteins affect chromatin structure, often in telomeric regions, and thereby affect transcription and silencing of various genes (Saunders, Chue, Goebl, Craig, Clark, Powers, Eissenberg, Elgin, Rothfield, and Earnshaw, 1993; Singh, Miller, Pearce, Kothary, Burton, Paro, James, and Gaunt, 1991; Trofatter, Long, Murrell, Stotler, Gusella, and Buckler, 1995). Small intranuclear proteins also participate in generating alternative splicing techniques of pre-mRNA and, by this mechanism, contribute to sexual differentiation in at least two species, Drosophila melanogaster and Caenorhabditis elegans (Adler and Hajduk, 1994; de Bono, Zarkower, and Hodgkin, 1995; Ge, Zuo, and Manley, 1991; Green, 1991; Parkhurst and Meneely, 1994; Wilkins, 1995; Wolfner, 1988). That similar proteins perform functions in humans suggests the possibility that some human sex differences may arise from alternative splicings of otherwise identical genes.

A potential ramification of epigenetic imprinting and alternative splicing may be occurring in Xq28, a chromosomal region implicated in homosexual orientation (Brook, 1993; Hu, Pattatucci, Patterson, Li, Fulker, Cherny, Kruglyak, and Hamer, 1995; Turner, 1995). Xq28 contains one of the X chromosome’s two pseudoautosomal regions (PARs), adjoins the telomere, and has various means of gene expression control (D’Esposito, Ciccodicola, Gianfrancesco, Esposito, Flagiello, Mazzarella, Schiessinger, and D’Urso (1996). Xq28, therefore, is a chromosomal region that has many of the heterochromatic and telomeric characteristics that participate in sexual determination and behavior in other species.

About James V. Kohl 1308 Articles
James Vaughn Kohl was the first to accurately conceptualize human pheromones, and began presenting his findings to the scientific community in 1992. He continues to present to, and publish for, diverse scientific and lay audiences, while constantly monitoring the scientific presses for new information that is relevant to the development of his initial and ongoing conceptualization of human pheromones. Recently, Kohl integrated scientific evidence that pinpoints the evolved neurophysiological mechanism that links olfactory/pheromonal input to genes in hormone-secreting cells of tissue in a specific area of the brain that is primarily involved in the sensory integration of olfactory and visual input, and in the development of human sexual preferences. His award-winning 2007 article/book chapter on multisensory integration: The Mind’s Eyes: Human pheromones, neuroscience, and male sexual preferences followed an award winning 2001 publication: Human pheromones: integrating neuroendocrinology and ethology, which was coauthored by disinguished researchers from Vienna. Rarely do researchers win awards in multiple disciplines, but Kohl’s 2001 award was for neuroscience, and his 2007 “Reiss Theory” award was for social science. Kohl has worked as a medical laboratory scientist since 1974, and he has devoted more than twenty-five years to researching the relationship between the sense of smell and the development of human sexual preferences. Unlike many researchers who work with non-human subjects, medical laboratory scientists use the latest technology from many scientific disciplines to perform a variety of specialized diagnostic medical testing on people. James V. Kohl is certified with: * American Society for Clinical Pathology * American Medical Technologists James V. Kohl is a member of: * Society for Neuroscience * Society for Behavioral Neuroendocrinology * Association for Chemoreception Sciences * Society for the Scientific Study of Sexuality * International Society for Human Ethology * American Society for Clinical Laboratory Science * Mensa, the international high IQ society