Chapter 13, Problem 3DAA

Summary Introduction

To explain: The strain of Salmonella typhi that was inhibited most by CFTR mutation.

Concept introduction: Allele is the modification of the gene. Salmonella typhi is the causative bacteria of typhoid. Cystic fibrosis (CF) is a genetic disorder due to inability of the cell to perform endocytosis due to mutation in the CFTR gene. Cystic fibrosis affects the lungs, intestine, liver, and kidneys. Endocytosis is a phenomenon where the cell takes up molecules by engulfing with its membrane. The S. typhi exploits this mechanism to infect the intestinal cell and cause diarrhea. The cells that are homozygous for this CFTR mutation cannot perform endocytosis, and the S. typhi cannot infect those individuals.