Bulk mRNA-sequencing of whole blood samples of first-episode schizophrenia patients and healthy controls

First-episode schizophrenia (FES) patients (n = 128) and healthy controls (HC) (n = 111) of Chinese Han ethnicity were enrolled in Beijing Huilongguan Hospital from 2016 to 2018. Whole bloodwas collected between 7 and 9 AM after overnight fasting using PAXgeneTM blood RNA tubes (Applied Biosystems, USA). Total RNAs were extracted using Mag-MAXTM RNA Isolation Kit (Applied Biosystems, USA). RNAs were quantified and assessed for purity by optical density ratios of 260nm/280nm and 260nm/230nm using NanoDrop spectrophotometry, and samples (1 µg) were immediately shipped on dry ice to the laboratory of the Beijing Genomics Institute (BGI), China for sequencing on the BGIseq-500 platform. Quality controls (QCs) on RNA samples (RIN/RQN = 7.0, 28S/18S = 1.0) were confirmed by BGI, followed by globin mRNA removal and cDNA library construction. Clean data of at least 4Gb (20M clean reads) per sample were collected.