Some of the most common diseases are infections caused by bacteria, such as Campylobacter, Salmonella, Shigella, E. coli O157:H7, Listeria, botulism, and norovirus.
A genotype is the actual genetic coding for an organism. A phenotype is the physical appearance. For example, let's say BB or Bb is the coding for black hair. BB/Bb is the genotype, and the black hair is the phenotype.
The Genotype is that part (DNA sequence) of the genetic makeup of a cell, and therefore of an organism or individual, which determines a specific characteristic (phenotype) of that cell/organism/individual. Conversely, some phenotypes could be the result of multiple genotypes. 2  The genotype is commonly mixed up with the Phenotype which describes the end result of both the genetic and the environmental factors giving the observed expression (e.g. blue eyes, hair color, or various hereditary diseases).