PT - JOURNAL ARTICLE AU - Pacheco, Jennifer AU - Beevers, Christopher G. AU - Benavides, Cristina AU - McGeary, John AU - Stice, Eric AU - Schnyer, David M. TI - Frontal-Limbic White Matter Pathway Associations with the Serotonin Transporter Gene Promoter Region (5-HTTLPR) Polymorphism AID - 10.1523/JNEUROSCI.0896-09.2009 DP - 2009 May 13 TA - The Journal of Neuroscience PG - 6229--6233 VI - 29 IP - 19 4099 - http://www.jneurosci.org/content/29/19/6229.short 4100 - http://www.jneurosci.org/content/29/19/6229.full SO - J. Neurosci.2009 May 13; 29 AB - Variation in the serotonin transporter gene-linked polymorphic region (5-HTTLPR) has been associated with heightened neural activity in limbic and prefrontal regions in response to emotional stimuli. The current study examined whether the 5-HTTLPR polymorphism is also associated with alterations in microstructure of frontal-limbic white matter (WM) tracts. Thirty-seven (mean age, 20.51 years; range, 13–28) female participants were genotyped for the 5-HTTLPR polymorphism. Diffusion MRI was collected and a probabilistically defined tract of the uncinate fasciculus (UF), a WM pathway connecting the amygdala to medial and orbital prefrontal cortex, was used to generate fractional anisotropy (FA) values for participants. Regression analyses indicated a significant inverse association between number of low-expressing 5-HTTLPR alleles and FA values for the left frontal UF region, β = − 0.42, p = 0.005. Furthermore, there was a positive association between age and FA values for bilateral frontal regions of the UF; these effects explained 39 and 20% of the variance in FA values for left and right frontal regions, respectively. 5-HTTLPR genotype and age appear to independently influence the WM microstructure of the UF. The observed reduction in FA values among low-expressing 5-HTTLPR allele carriers may contribute to biased regulation of emotional stimuli.