Assessing the association between cytokine-related genes and facial appearance

Abstract

Extensive research has been directed towards assessing the belief that facial appearance indicates health, particularly immunity. Many studies have linked facial appearance in the non-clinical populations with various health parameters such as self-reported health, cardiovascular health and even direct measures immunity such as response to hepatitis B vaccinations and cytokine response. There has also been direct evidence that genes associated with the immune response influence facial appearance in men. Being a genetics student I was particularly curious in the genetic link between facial appearance and health. The HLA genes are the only genes that have been investigated to determine this link and they represent a relatively small portion of the immune system. Cytokine genes were chosen as candidates for this dissertation to understand how immune based genes may influence facial appearance. Cytokines are good candidates as they play a vital role from start to finish in the entire immune response as well as general immune homeostasis. This dissertation comprises of three chapters. Chapter one is a brief overview of the literature. Particular interest was given to (a) the importance of facial appearance in everyday life and in various fields of research, (b) to previous studies that assessed the genetic variants which influence facial appearance in non-clinical populations and (c) specific relationships between facial appearance and health. The general immune response was also investigated and particular focus was given to cytokines and the specific candidate cytokines that were used in this study. Chapter two is the research chapter in which I investigated the relationship between candidate cytokine-related SNPs and facial appearance. The chapter was divided into two experiments with each experiment assessing different facial appearance variables. In experiment one I determined the health appearance of facial images and the facial cues that influence health appearance. In experiment two I measured structural components of the face. In Chapter three I summarised the results and importance of this study, acknowledged the challenges and limitations as well as indicate suggestions for future studies.