Pharmacogenetics and genetic predisposition
The genetic predisposition or genetic susceptibility means the genetic mass able to influence in the phenotype of a person, population or species. Phenotype is known as the expression of the genotype (from DNA) dependent on the environment. It’s the visible manifestation of the genotype and it refers to any characteristic or trait of a person; it involves morphology, physiology, behavior, biochemical properties, etc.
Therefore, genetic predisposition is the increase or decrease of the probability of illness depending on genetics. Through simple nucleotide polymorphisms (SNPs) and following a multiplicative mathematical model with exceptions as haplotypes, it is possible to calculate the risk that a particular person could have in developing a disease, using incidence and allele frequencies.