Gender differences in association between serotonin transporter gene polymorphism and resting-state EEG activity

Area of Science:

• Neuroscience
• Genetics
• Psychiatry

Background:

• Human brain oscillations are crucial for information processing and are highly heritable.
• The 5-HTTLPR polymorphism is linked to various endophenotypes, with gender influencing these associations.

Purpose of the Study:

• To investigate the effects of the 5-HTTLPR polymorphism on spontaneous electroencephalography (EEG) activity in healthy males and females.
• To explore gene by sex interactions in the modulation of resting brain activity.

Main Methods:

• Collected DNA from buccal swabs and resting EEG data from 210 healthy volunteers (101 men, 109 women).
• Analyzed spectral EEG power estimates and cortical sources of EEG activity across 60 standard leads.
• Investigated genotype differences in electrical brain activity, considering gender as a variable.

Main Results:

• 5-HTTLPR polymorphism effects on EEG activity significantly varied by gender.
• Women with the S/L genotype exhibited greater global EEG power than men with the same genotype.
• Significant gender-specific differences in current source density were observed in various brain regions and frequency bands, particularly in the parietal and postcentral areas.

Conclusions:

• The study demonstrates a significant gene by sex interaction on resting EEG activity.
• These findings have implications for understanding sex-related differences in affective states, emotion, and cognition.
• The 5-HTTLPR polymorphism modulates EEG activity differently across genders, highlighting the importance of considering sex in neurogenetic research.