Intergenerational transfer of cognitive phenotypes from Lamarck theory to epigenetic mechanisms

The notion that non-genetic and non-cultural mechanisms can transmit the memory of exposure to diverse environmental conditions to subsequent generations has excited considerable interest and has brought the Lamarck’s idea back into the limelight. It is widely accepted that the environmental experiences of parents have strong effects on the physiological, metabolic, and cellular functions of living organisms, which are transmitted through epigenetic modifications to the next generations. The epigenetic modifications prone to change in environmental conditions and transmitted to next generations include DNA methylation, histone modification, and small non-coding RNAs. Currently, one of the most exciting topics in the field of epigenetic transmission is the transfer of memory phenotypes and learning and memory capabilities. Inheriting epigenetic traits allows living organisms to transmit compatible or incompatible information with the ancestral environment to their offspring. Studies showed that exposure to environmental stimuli by parents before fertilization would lead to changes in their childrenchr('39')s cognitive capacities. Interestingly, learning cognitive tasks in parents improved the learning and facilitated memory consolidation in offspring. The methylation DNA, histone methylation and histone acetylation are three major epigenetic processes involved in the regulation of learning and memory consolidation. These processes modify genome features or interactions between the genome and the histone nucleus, and then induce structural changes in chromatin, leading to transcriptional changes in various genes that affect memory formation. The transfer of these chromatin modifications from parents to offspring facilitates the offspring learning process and memory consolidation.