It should be noted that although the OXT gene contributes directly to the production of the oxytocin precursor, variation in this gene does not appear to affect behavioral outcomes and characteristics as much as variation in the receptor (e.g., OXTR gene), which encodes a receptor protein conveying oxytocin’s signal to receptive cells. To operationalize OXTR gene variance, we used multiple markers within OXTR, following the example of Schneiderman, Kanat-Maymon, Ebstein, & Feldman (2013) who studied of the association between OXTR variation and empathetic communication at the beginning of loving romantic relationships. Similar to Schneiderman and colleagues’ cumulative OXTR genetic risk score, ours is a multi-SNP single-gene index where variation in each of 5 OXTR Single Nucleotide Polymorphisms (SNPs) contributes additively to the overall gene score.
