Characterization of loss of Y chromosome in peripheral blood of Chinese Han male patients with schizophrenia

Abstract Background Schizophrenia has a global prevalence of 1% and is a threat to life expectancy and mortality. There is growing evidence that the risk of developing this disorder is higher in males than in females and tends to develop in early adulthood. The Y chromosome is thought to be involved in biological processes other than sex determination and spermatogenesis that affect male health and disease. Studies have found that Loss of Y chromosome (LOY) in peripheral blood is associated with a variety of diseases, cancer and increased all-cause mortality, so an analysis of the relationship between LOY and schizophrenia is warranted. Methods The study included 442 Chinese males (271 patients with schizophrenia vs 171 controls). The copy numbers of Y and X chromosome were detected by the positive droplets targeted with Amelogenin gene (AMEL) located on the Y chromosome and X chromosome (AMELY and AMELX) using droplet digital PCR (ddPCR), respectively. The LOY percentage was defined as the difference between the concentration of AMELX and the concentration of AMELY divided by the concentration of AMELX, denoted as (X - Y)/X. Results There was no significant difference in the presence of LOY between the schizophrenia and control groups in Chinese Han population. A remarkable correlation was found between the disease duration and (X - Y)/X ratio by using the mean (R 2 = 0.51, p = 0.032). The logistic regression analysis implied that the risk of suffering LOY increases by 5.8% and 5.7% per year with age at onset and duration of the disease, respectively ( p onset = 0.013, p duration = 0.017). Conclusions For the Chinese Han population, age of onset and duration of schizophrenia might be risk factors for LOY development in peripheral blood. More clinical information and larger sample size need to be collected for more in-depth and specific analyses.