A cis-eQTL in AHI1 confers risk to schizophrenia in European populations.

Schizophrenia is a devastating mental disorder, with heritability as high as 80%. Although genome-wide association studies have identified multiple promising risk variants of schizophrenia, they could only explain a small portion of the disease heritability, and other variants with low to moderate effect remain to be identified. Abelson helper integration site 1 (AHI1) is highly expressed in mammals throughout the developing brain, with lower expression continuing into adulthood. Besides, previous evidence suggested that AHI1 expression was changed in schizophrenia patients. Furthermore, association signal between AHI1 variants and schizophrenia has been reported in several European samples. In the present study, we first analyzed two expression quantitative trait loci (eQTL) datasets in healthy individuals and investigated the associations of eQTL of AHI1 with schizophrenia in independent European samples. We observed that a cis-eQTL of AHI1, rs11154801, showed significant association with AHI1 expression in both datasets (P<5E-05). Genetic evidence exhibited that rs11154801 was significantly associated with schizophrenia risk in both the discovery sample (9394 cases and 12462 controls, P=0.046, OR=0.958, 95% CI=0.918-0.999) and the replication sample (3240 cases and 14786 controls, P=0.024, OR=0.949, 95% CI=0.870-0.990). When the discovery and replication samples were pooled together, this association was further strengthened (P=0.004, OR=0.949, 95% CI=0.916-0.983). These results suggested that AHI1 is likely a risk gene for schizophrenia, at least in European populations.

Sleep-related breathing disorder is associated with hyperactivity in preschoolers.

INTRODUCTION: Sleep problems are a prominent feature in children with attention deficit hyperactivity disorder (ADHD). Unlike existing studies that focused on extreme samples (i.e. normal vs. ADHD), our study investigated the associations of sleep-related behaviours and ADHD features in nonclinical Chinese preschoolers. METHODS: All participants were recruited via advertisements and screened for eligibility through a telephone interview prior to an onsite visit. The maternal reports of the Conners' Parent Rating Scale (CPRS) and Pediatric Sleep Questionnaire (PSQ) were acquired from 110 Chinese preschoolers aged six years. Regression models were used to examine the association between CPRS and PSQ scores. RESULTS: The results obtained from regression models on the CPRS and PSQ scores of the 110 participants showed that none of the sleep-related behavioural measures (i.e. sleep-related breathing disorder [SRBD], snoring, daytime sleepiness, restless legs syndrome) was associated with inattention in our sample. However, worse SRBD was associated with higher hyperactivity. CONCLUSION: Our study underpins the importance of understanding the relationship between sleep-related behaviours and ADHD characteristics before the usual age of clinical diagnosis in children with ADHD.