5-HTTLPR seems to correspond to the SNPs rs25531 and rs25532 (both of which are included in the most recent chip used by 23andme).
The same paper has been the topic of a previous discussion post.
Sorry about the redundant post. I would delete it, but I feel that Jayson_Virissimo's comment is worth archiving.
Thank you! I spent like five minutes looking for that and couldn't find it: I was ctrl+F-ing for [link].
A new link is found between serotonin transporters and philosophical predispositions.