Note: As a Portuguese descendant born in Brazil, I have always felt a strong emotional bond with Portugal, even though I have never visited the country. My family is originally from Madeira Island, and when visiting the island for the first time, I felt a deep and inexplicable connection, as if it were my ancestral home. Subsequent investigations revealed that my lineage dates back to the island’s first settlers, with ancestors who had settled there since the beginning of Portuguese colonization, coming from the mainland. This phenomenon led me to investigate the origin and biological basis of genetic memory.
Scientific Proof on Genetic and Transgenerational Memory
The hypothesis that memories can be transmitted from generation to generation through epigenetic mechanisms, such as histone modifications, has been widely studied. Epigenetic modifications, such as histone methylation and acetylation, play a crucial role in regulating gene expression and maintaining transcriptional states across cellular generations.
1. Inheritance of Histone Modifications :
Studies demonstrate that certain histone modifications, such as methylation of lysine 4 on histone H3 (H3K4me2), can be inherited across multiple cell divisions, serving as an epigenetic mark that facilitates rapid reactivation of previously repressed genes. This inheritance mechanism is mediated by interactions between H3K4me2 reader proteins and histone writing complexes, such as SET3C and Spp1-COMPASS (Brickner, 2023).
2. Epigenetic Inheritance Independent of the DNA Sequence:
Research with the yeast Schizosaccharomyces pombe has revealed that histone modifications, such as H3K9 methylation, can be transmitted through mitotic and meiotic generations regardless of DNA sequence. This process is mediated by histone reading and writing mechanisms that allow the maintenance of epigenetic states even in the absence of DNA sequence-dependent initiating signals (Ragunathan et al., 2015).
3. Impact of Histone Modifications on Transgenerational Health:
Overexpression of a histone demethylase in mouse sperm demonstrated that changes in H3K4 methylation during spermatogenesis can result in developmental anomalies and reduced viability in three subsequent generations. This study suggests that histone methylation and altered sperm RNA are potential mediators of transgenerational epigenetic inheritance (Siklenka et al., 2015).
4. Epigenetic memory in C. elegans :
In Caenorhabditis elegans, spermatozoa were observed to retain nucleosomes with histone modifications that reflect the epigenetic memory of genes expressed during spermatogenesis. These epigenetic marks are important for the proper development of germ cells in offspring, demonstrating a histone-based form of paternal epigenetic inheritance (Tabuchi et al., 2018).
These studies provide a solid foundation for understanding how epigenetic memories can be passed down through generations and influence the health and behavior of offspring. Epigenetic regulation, especially through histone modifications, emerges as a fundamental mechanism in the inheritance of acquired traits and the maintenance of cellular identity.
References :
– BRICKNER, Jason H. Inheritance of epigenetic transcriptional memory through read–write replication of a histone modification. Annals of the New York Academy of Sciences, vol. 1526, p. 50-58, 2023.
– RAGUNATHAN, K.; JIH, Gloria T.; MOAZED, D. Epigenetic inheritance uncoupled from sequence-specific recruitment. Science, vol. 348, 2015.
– SIKLENKA, Keith et al. Disruption of histone methylation in developing sperm impairs offspring health transgenerationally. Science, vol. 350, 2015.
– TABUCHI, T. et al. Caenorhabditis elegans sperm carry a histone-based epigenetic memory of both spermatogenesis and oogenesis. Nature Communications, vol. 9, 2018.
Dr. Fabiano de Abreu Agrela Rodrigues MRSB holds a post-PhD in Neuroscience and is an elected member of Sigma Xi – The Scientific Research Honor Society (more than 200 members of Sigma Xi have received the Nobel Prize), as well as being a member of the Society for Neuroscience in the United States, the Royal Society of Biology and The Royal Society of Medicine in the United Kingdom, the European Society of Human Genetics in Vienna, Austria, and the APA – American Philosophical Association in the United States. He holds a Master’s degree in Psychology and a Bachelor’s degree in History and Biology. He is also a Technologist in Anthropology and Philosophy, with several national and international degrees in Neuroscience and Neuropsychology. Dr. Fabiano is a member of prestigious high IQ societies, including Mensa International, Intertel, ISPE High IQ Society, Triple Nine Society, ISI-Society, and HELLIQ Society High IQ. He is the author of more than 300 scientific studies and 30 books. He is currently a visiting professor at PUCRS in Brazil, UNIFRANZ in Bolivia and Santander in Mexico. He also serves as Director of CPAH – Centro de Pesquisa e Análises Heráclito and is the creator of the GIP project, which estimates IQ through the analysis of genetic intelligence. Dr. Fabiano is also a registered journalist, having his name included in the book of records for achieving four records, one of which is for being the greatest creator of characters in the history of the press.