Depressed? Siberian scientists have figured out the gene combinations to blame

Research headed by Dr Tatyana Axenovich is using statistical methods for genetic analysis, creating software to identify the genes responsible for particular conditions.

Deploying computers rather than microscopes, Siberian scientists use collections of genomes available to other research groups. The results can be groundbreaking. 

This happened with data obtained from Dutch centre 'Erasmus' in Rotterdam, where experts study depression, one of the most common mental conditions of our time.

Dr Axenovich said: 'From the point of view of genetics, depression is a unique disorder. The contribution of genotype in the development of depression is about the same as that of schizophrenia. 

'But for schizophrenia dozens of genes are already found that control the onset and development of this disease. There was no single gene firmly established for depression.' 

She said this is due to the peculiarities of the disorder. 

It has a variety of manifestations. Patients vary in frequency, severity and duration of episodes. Depression is characterized by a complex genetic architecture, consisting of a large number of genes with small effects. It is known that the smaller the effect of the gene, the larger is the number of samples required for its identification. According to some estimates, to identify the genes responsible for depression some 50,000 people should be examined. 

But the scientists at the Institute of Cytology and Genetics achieved significant results after analysing around 2,000 sufferers, by using 'unique' methods and software.

'We did not consider each genetic variant alone, as is customary in this type of research,' she said. 'Instead, we took the whole gene. Furthermore, we  considered only those genetic variants that alter the structure of the corresponding protein. Another 'trick' is that we studied not the diagnosis, but focused on the so-called depressive symptoms.'

In the course of this work, the scientists identified a gene involved in the control of depression. It is known as NKPD1. Dutch researchers confirmed this result in an independent set of samples, which makes it 'credible'.