Exploring the association between SNPs and facial morphology in a Spanish population.

Understanding and predicting human external phenotypes, particularly facial shape, is of great value for individual identification. However, facial morphology is a highly complex trait. Despite its complexity, recent genome wide association studies (GWAS) have shed light on potential SNPs associated with facial features, offering a first glimpse into the likely genetic background of individual appearance. In this paper we have selected a set of 116 candidate SNPs and studied their association with facial phenotypes in a Spanish population of 412 individuals, highlighting a wide spectrum of facial morphologies worthy of investigation. We performed canonical correlation analysis (CCA) between each SNP and the observed spacial variation in facial shape, from its representation by a dense mesh of 7160 quasi-landmarks, revealing significant associations within different facial segments. In particular, ten SNPs are highlighted for their strong association within this Spanish population, some of them uncovering correlations with novel facial regions. These findings underline the importance and usefulness of conducting candidate SNP studies, not only to validate existing associations but also to unveil novel correlations within subpopulations.