Chapter 17, Problem 28ESP

Summary Introduction

To explain: The reason due to which a mutation near, but outside of the coding region of Pitx1 gene may cause a loss of pelvic fins in lake population of stickleback fish without any pleiotropic effect on the pituitary gland and jaw.

Introduction: The transcription of eukaryotic genes is influenced by DNA sequences called enhancers. Enhancers are cis-regulatory like the promoters because they regulate genes on the same chromosome. The promoters are required for basal level transcription while the enhancers increase the rate of transcription. Enhancers are also important for tissue-specific gene expression.