Even though the causes of depression have not been fully identified yet, the scientific community agrees to affirm that it is produced by a combination of genetic and environmental factors. One of the environmental risk factors that is more commonly related to depression is the exposure to traumatic experiences. On the other hand, from the genetic point of view, the serotonin transporter gene (an essential neurotransmitter in the communication between neurons) could predispose some individuals to depression.
An international group of scientists, headed by Jorge Cervilla Ballesteros and Blanca Gutiérrez Martínez, lecturers of the Department of Legal Medicine, Toxicology and Psychiatry of the University of Granada (Universidad de Granada), has recently published this pioneering study called PREDICT-gene in the prestigious journal Molecular Psychiatry. This study confirms the connection between the s allele in the serotonin transporter gene and the exposure to traumatic experiences in the onset of depression.
The study confirms that, in a sample of population which takes into account factors such as gender, age and the family case history of psychiatric disorders, 24% of the Spanish population, who have the s/s genotype, need a lower exposure to traumatic experiences to develop depression, unlike subjects with s/l or l/l genotypes. Therefore, the research reaffirms the connection between genetic and environmental factors in this mental disorder.
Tailor-made antidepressants
The most important consequence of these studies about genetic-environmental interactions is that, in the not too distant future, prediction measures to antidepressant response could be created according to each individual’s genotype, that is, personalised drugs could be designed, taking into account the genetic configuration of each person and their exposure to environmental factors.
Nowadays, the team of lecturers Cervilla Ballesteros and Gutiérrez Martínez is opening a path in the psycho-medical-genetics field in the University of Granada, a path which will allow the creation of individualised treatments, tailor-made for each patient suffering from depression, a very common disorder which affects one out of every five Spaniards visiting the doctor.
The study, which forms part of the international project PREDICT and is funded by the European Union and the Spanish Ministry of Education and Science, is the article with the greatest impact in the scientific history of the Andalusian psychiatry. One of the most important novelties that it contributes is that it has been carried out through a very representative sample of population: 737 subjects took part in the genetic tests, with ages between 18 and 75 years old; all of them patients of nine Primary Health Care Centres of the province of Malaga. Because of that, it is the first representative study based on samples of population which manages to reproduce the results of previous studies carried out in restricted samples of population comprising only women, teenagers, twins or patients with affective disorders.
References
Prof. Jorge Cervilla Ballesteros. ‘Federico Olóriz’ Neuroscience Institute, Universidad de Granada.
Telephones: 958 24 20 17 / 663 07 58 35. E-mail: jacb@ugr.es
Prof. Blanca Gutiérrez Martínez. ‘Federico Olóriz’ Neuroscience Institute, Universidad de Granada.
Telephones: 958 24 20 75 / 676 44 46 77. E-mail: blancag@ugr.es