Genetic factors predispose metabolic syndrome in mixed races

Under the lead of Lorena Orozco, the objective of the research is to know the genetic susceptibility of the mixed and indigenous Mexican populations to developing metabolic syndrome or one of its components and the relationship of this risk with its indigenous, Caucasian or African origins.

The researcher explained that the metabolic syndrome is characterized by the simultaneous presence or sequence of at least three of the next components: increment in glucose levels, triglycerides, arterial hypertension, low levels of benefic cholesterol (HDL) and rise of the waist circumference.

She also said that the study includes individuals from different Mexican states throughout the country, like Chiapas, San Luis Potosí, Mexico State, Yucatán, Chihuahua, Oaxaca, Puebla and Mexico City.

The project's study group was integrated by 800 mixed race individuals and 400 natives more than 30 years old, from both sexes. Blood samples were taken from this groups in order to know their cholesterol, triglycerides, glucose and blood pressure levels, as well as their body mass, size, weight and height.

In this stage of the study, it was founded that 42 per cent of the mixed population suffered from metabolic syndrome and 10 per cent had type II diabetes.

Regarding the indigenous group, the results showed that there were communities like the Tojolabales form Chiapas, where type II diabetes was barely present, contrasting with other groups like the Totonacas from Veracruz, were the prevalence of this disease was near a 25 per cent. It was also found that 45 per cent of the Tarahumaras from Chihuahua that were tested had high blood pressure.

In another phase of the project, DNA from each individual was analyzed to evaluate the intervention of three genes (AKT1, GCKR and ADIPOQ) that participate in the metabolism of glucose or fatty acids.

"We are heirs of a genetics that in a hostile environment, thousands of years ago, helped us survive long periods of famine and other hardships. However, in the present, this genetics is the detonator of diseases such as diabetes, obesity and metabolic syndrome," emphasized the researcher.

Regarding the main discoveries, the researchers observed that in the mixed population there are variations in the sequence of ADIPOQ and GCKR genes that are associated to the rise of triglycerides in the blood stream. Meanwhile, the variations of the gene AKT1 are related with low levels of benefic cholesterol.

Another important discovery was that the genetic variations in the AKT1 gene come mainly from the Caucasian component of the mixed-Mexican population, whereas in the case of ADIPOQ and GCKR genes the mutations are integrated by indigenous and Caucasian origins.

According to the researcher, the next stage of the project is to expand to 400 more individuals in both groups. By detecting genetic variations in mixed and indigenous populations that are in risk of developing metabolic syndrome, future models of treatment can be made more efficient and even a predictive diagnosis of the disease could be implemented.

Globally, the prevalence of the metabolic syndrome is between 30 and 50 per cent of the population and in Mexico it reaches a 42 per cent, the women having a greater probability of manifesting it.