Polygenic contributions to performance on the Balloon Analogue Risk Task.

Risky decision-making is a common, heritable endophenotype seen across many psychiatric disorders. Its underlying genetic architecture is incompletely explored. We examined behavior in the Balloon Analogue Risk Task (BART), which tests risky decision-making, in two independent samples of European ancestry. One sample (n = 1138) comprised healthy participants and some psychiatric patients (53 schizophrenia, 42 bipolar disorder, 47 ADHD); the other (n = 911) excluded for recent treatment of various psychiatric disorders but not ADHD. Participants provided DNA and performed the BART, indexed by mean adjusted pumps. We constructed a polygenic risk score (PRS) for discovery in each dataset and tested it in the other as replication. Subsequently, a genome-wide MEGA-analysis, combining both samples, tested genetic correlation with risk-taking self-report in the UK Biobank sample and psychiatric phenotypes characterized by risk-taking (ADHD, Bipolar Disorder, Alcohol Use Disorder, prior cannabis use) in the Psychiatric Genomics Consortium. The PRS for BART performance in one dataset predicted task performance in the replication sample (r = 0.13, p = 0.000012, pFDR = 0.000052), as did the reciprocal analysis (r = 0.09, p = 0.0083, pFDR=0.04). Excluding participants with psychiatric diagnoses produced similar results. The MEGA-GWAS identified a single SNP (rs12023073; p = 3.24 × 10-8) near IGSF21, a protein involved in inhibitory brain synapses; replication samples are needed to validate this result. A PRS for self-reported cannabis use (p = 0.00047, pFDR = 0.0053), but not self-reported risk-taking or psychiatric disorder status, predicted behavior on the BART in our MEGA-GWAS sample. The findings reveal polygenic architecture of risky decision-making as measured by the BART and highlight its overlap with cannabis use.

BMPR2 mutations in pulmonary arterial hypertension with congenital heart disease.

The aim of the present study was to determine if patients with both pulmonary arterial hypertension (PAH), due to pulmonary vascular obstructive disease, and congenital heart defects (CHD), have mutations in the gene encoding bone morphogenetic protein receptor (BMPR)-2. The BMPR2 gene was screened in two cohorts: 40 adults and 66 children with PAH/CHD. CHDs were patent ductus arteriosus, atrial and ventricular septal defects, partial anomalous pulmonary venous return, transposition of the great arteries, atrioventicular canal, and rare lesions with systemic-to-pulmonary shunts. Six novel missense BMPR2 mutations were found in three out of four adults with complete type C atrioventricular canals and in three children. One child had an atrial septal defect and patent ductus arteriosus; one had an atrial septal defect, patent ductus arteriosus and partial anomalous pulmonary venous return; and one had an aortopulmonary window and a ventricular septal defect. Bone morphogenetic protein receptor 2 mutations were found in 6% of a mixed cohort of adults and children with pulmonary arterial hypertension/congenital heart defects. The current findings compliment recent reports in mouse models implicating members of the bone morphogenetic protein/transforming growth factor-beta pathway inducing cardiac anomalies analogous to human atrioventricular canals, septal defects and conotruncal congenital heart defects. The small number of patients studied and the ascertainment bias inherent in selecting for pulmonary arterial hypertension require further investigation.

The effect of intercondylar notchplasty on the patellofemoral articulation.

Using pressure-sensitive film, we measured the patellofemoral contact areas and pressures after increasing degrees of notchplasty in eight fresh-frozen cadaveric knee specimens. Each specimen was stabilized on an axial loading frame with physiologic loads applied through the quadriceps tendon at varying flexion angles. The patellofemoral joint was loaded at 90 degrees, 105 degrees and 120 degrees of knee flexion. The same measurements were then obtained after serial notchplasties of 3, 6, and 9 mm. The film was analyzed for contact areas and for contact pressures by densitometry. There was no statistical significance between contact area or pressure after notchplasties of 3, 6, or 9 mm at 90 degrees, 105 degrees, and 120 degrees of knee flexion. These data suggest that routine notchplasty does not affect the patellofemoral articulation.

A unique complication following arthroscopic anterior cruciate ligament reconstruction.

The use of the middle third of a patellar tendon with bone blocks is a common and well-accepted technique for arthroscopic reconstruction of the anterior cruciate ligament. We report here a disconcerting fracture/avulsion pattern of the patella/patellar tendon mechanism that occurred in the early postoperative period.