<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Depression is estimated to affect 350 million people worldwide. The World Mental Health Survey conducted in 17 countries found that, on average, about one in 20 people reported having an episode of depression in the previous year. Although depression has been shown to be moderately heritable by studies conducted in the past, the search for its so-called missing heritability has so far been unsuccessful. The difficulty in identifying common genetic variants predisposing to depression could be due to large sample sizes needed to detect small effects on genetic risk and the heterogeneous nature of major depressive disorder (MDD). The aim of our study was to determine whether there was a connection between a family history of depression in MDD patients and the presence of putative risk variants in the well-studied <italic>SLC6A4</italic>, <italic>COMT</italic> and <italic>PCLO</italic> genes. We analyzed 133 patients with MDD (30.0% with a positive family history for MDD and 70.0% sporadic cases) and compared them to 279 healthy controls. When comparing all the depressed patients to controls, no significant differences in genotype and allele distributions were detected. After stratifying patients according to their family history, the <italic>PCLO</italic> rs2522833 C allele was shown to be significantly less common in patients with a positive family history (<italic>p</italic> = 0.001), indicating a possible difference in the genetic structure of MDD between familial and sporadic cases and a less important role of the common genetic risk variants for the development of MDD in familial cases.</p></abstract>

Depression is estimated to affect 350 million people worldwide. The World Mental Health Survey conducted in 17 countries found that, on average, about one in 20 people reported having an episode of depression in the previous year. Although depression has been shown to be moderately heritable by studies conducted in the past, the search for its so-called missing heritability has so far been unsuccessful. The difficulty in identifying common genetic variants predisposing to depression could be due to large sample sizes needed to detect small effects on genetic risk and the heterogeneous nature of major depressive disorder (MDD). The aim of our study was to determine whether there was a connection between a family history of depression in MDD patients and the presence of putative risk variants in the well-studied SLC6A4, COMT and PCLO genes. We analyzed 133 patients with MDD (30.0% with a positive family history for MDD and 70.0% sporadic cases) and compared them to 279 healthy controls. When comparing all the depressed patients to controls, no significant differences in genotype and allele distributions were detected. After stratifying patients according to their family history, the PCLO rs2522833 C allele was shown to be significantly less common in patients with a positive family history (p = 0.001), indicating a possible difference in the genetic structure of MDD between familial and sporadic cases and a less important role of the common genetic risk variants for the development of MDD in familial cases.

Family history as an important factor for stratifying participants in genetic studies of major depression

University Psychiatric Hospital Ljubljana

Balkan Journal of Medical Genetics

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Depression is estimated to affect 350 million people worldwide. The World Mental Health Survey conducted in 17 countries found that, on average, about one in...

Family history as an important factor for stratifying participants in genetic studies of major depression

Article Category: Original Article

Published Online: Oct 29, 2018

Page range: 5 - 12

DOI: https://doi.org/10.2478/bjmg-2018-0010

Keywords
gene, Family history, Major depressive disorder (MDD), gene, gene

© 2018 Zalar B, Blatnik A, Maver A, Klemenc-Ketiš Z, Peterlin B, published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Family history as an important factor for stratifying participants in genetic studies of major depression

Article Category: Original Article

Published Online: Oct 29, 2018

Page range: 5 - 12

DOI: https://doi.org/10.2478/bjmg-2018-0010

Keywordsgene, Family history, Major depressive disorder (MDD), gene, gene

© 2018 Zalar B, Blatnik A, Maver A, Klemenc-Ketiš Z, Peterlin B, published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
gene, Family history, Major depressive disorder (MDD), gene, gene