  Objectives: A series of meta-analyses assessed whether differentially
efficacious variants (CAG and GGC repeat-length polymorphisms) of the human
androgen receptor gene are associated with digit ratio (2D:4D), a widely
investigated putative pointer to prenatal androgen action. Methods: Extensive
literature search strategies identified a maximum of 16 samples (total N =
2157) eligible for meta-analysis. Results: In contrast to a small-sample (N =
50) initial report, widely cited affirmatively in the literature, meta-analysis
of the entire retrievable evidence base did not support associations between
androgen receptor gene efficacy and 2D:4D. Conclusions: These meta-analytical
nil findings, along with several further suggestive strands of evidence
consistent with these, undermine one validity claim for 2D:4D as a
retrospective pointer to prenatal testosterone action.
