Page 124 - Genomic Medicine in Emerging Economies

Introduction 113

behavior, hyperactivity, aggression, and executive function. Brazil, Colombia,
and Mexico have made major contributions to the knowledge about genetics
and endophenotypes in Latin American samples.

Pharmacogenetics and Neuropsychiatric Disorders in Latin
America
Pharmacogenomics applied to NPDs will help to implement genomics in the
care of neuropsychiatric patients in Latin America by predicting, based on the
individual genetic profiles, whether a drug will treat the disease or whether a
patient has a predisposition to adverse events (Suarez-Kurtz and Pena, 2006).
In addition, this research will help with clinical decisions, such as the best drug
and dosage for an individual, decreasing the time and costs of identifying the
right pharmacological treatments. The first step in pharmacogenetics research
is to identify the genetic variants that determine the response to a drug and to
determine if the findings in other populations can be applied to the different
samples of patients in the Latin America region (Suarez-Kurtz and Pena, 2006).
As molecular genetic factors are important variables for the response to
pharmacological compounds used for the treatment of NPD, several stud-
ies on pharmacogenetics have been carried out in Latin American countries
(Table 6.5), particularly in Mexico and Brazil. These studies have included
ADHD, BP, MDD, OCD, and SZ patients, testing the effect of variants on candi-
date genes (such as DRD1, SLC6A4, and MAOA, among others) to the response
of drugs such as methylphenidate, clozapine, and lithium (Bruxel et al., 2015;
Bruxel et al., 2013; Contini et al., 2011, 2010; Corregiari et al., 2012; da Silva
et al., 2008; Gonzalez-Covarrubias et al., 2016; Guimaraes et al., 2009b; Kohl-
rausch et al., 2008a,b; Kohlrausch et al., 2010, 2013; Michelon et al., 2006; Ota
et al., 2012; Peñas-lledó et al., 2013; Polanczyk et al., 2007; Salatino-Oliveira
et al., 2011; Zeni et al., 2007). Most of the studies on neurological disorders
focused on epilepsy and aimed to estimate the allele and genotype frequencies
of markers influencing the effects of antiepileptic drugs, evaluating if these fre-
quencies were different between the Mexican-Mestizo populations and other
reported samples (Fricke-Galindo et al., 2016). There are no studies on epigen-
etic markers as possible predictors of response to pharmacological treatments
on NPDs in Latin America (Reynolds and Fachim, 2016).
To assess whether findings from other populations can be extrapolated to the
samples from Latin America, there have been several studies and initiatives,
which have estimated the frequency of the most relevant pharmacogenetic bio-
markers for neuropsychiatric and metabolic phenotypes, in healthy volunteers
from Latin American populations and have compared them to the frequen-
cies observed in other samples around the world (Bonifaz-Pena et al., 2014;
Cespedes-Garro et al., 2015; Rodeiro et al., 2012; Suarez-Kurtz, 2004).