Association of Intronic Variants of the BTBD9 Gene With Tourette Syndrome
ARCHIVES OF NEUROLOGY
Authors: Riviere, Jean-Baptiste; Xiong, Lan; Levchenko, Anastasia; St-Onge, Judith; Gaspar, Claudia; Dion, Yves; Lesperance, Paul; Tellier, Geneieve; Richer, Francois; Chouinard, Sylvain; Rouleau, Guy A.
Abstract
Objective: To test the association between Tourette syndrome (TS) and genetic variants in genomic loci MEIS1, MAP2K5/LBXCOR1, and BTBD9, for which genome-wide association studies in restless legs syndrome and periodic limb movements during sleep revealed common risk variants. Design: Case-control association study. Setting: Movement disorder clinic in Montreal. Subjects: We typed 14 single-nucleotide polymorphisms spanning the 3 genomic loci in 298 TS trios, 322 TS cases (including 298 probands from the cohort of TS trios), and 290 control subjects. Main Outcome Measures: Clinical diagnosis of TS, obsessive-compulsive disorder, and attention-deficit disorder. Results: The Study provided 3 single-nucleotide polymorphisms within BTBD9 associated with TS (chi(2)=8.02 [P=.005] for rs9357271.), with the risk alleles for restless legs syndrome and periodic limb movements during sleep overrepresented in the TS cohort. We stratified our group of patients with TS according to presence or absence of obsessive-compulsive disorder and/or attention-deficit disorder and found that variants in BTBD9 were strongly associated with TS without obsessive-compulsive disorder (chi(2)= 12.95 [P<.001] for rs9357271). Furthermore, allele frequency of rs935727.1. inversely correlated with severity of obsessive-compulsive disorder as measured by the Yale-Brown Obsessive Compulsive Scale score. Conclusion: Variants in BTBD9 that predispose to restless legs syndrome and periodic limb movements during sleep are also associated with TS, particularly, TS without obsessive-compulsive disorder.
Streamlining the Pipeline for Generation of Recombinant Affinity Reagents by Integrating the Affinity Maturation Step
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
Authors: Huang, Renhua; Gorman, Kevin T.; Vinci, Chris R.; Dobrovetsky, Elena; Graeslund, Susanne; Kay, Brian K.
Abstract
Often when generating recombinant affinity reagents to a target, one singles out an individual binder, constructs a secondary library of variants, and affinity selects a tighter or more specific binder. To enhance the throughput of this general approach, we have developed a more integrated strategy where the affinity maturation step is part of the phage-display pipeline, rather than a follow-on process. In our new schema, we perform two rounds of affinity selection, followed by error-prone PCR on the pools of recovered clones, generation of secondary libraries, and three additional rounds of affinity selection, under conditions of off-rate competition. We demonstrate the utility of this approach by generating low nanomolar fibronectin type III (FN3) monobodies to five human proteins: ubiquitin-conjugating enzyme E2 R1 (CDC34), COP9 signalosome complex subunit 5 (COPS5), mitogen-activated protein kinase kinase 5 (MAP2K5), Splicing factor 3A subunit 1 (SF3A1) and ubiquitin carboxyl-terminal hydrolase 11 (USP11). The affinities of the resulting monobodies are typically in the single-digit nanomolar range. We demonstrate the utility of two binders by pulling down the targets from a spiked lysate of HeLa cells. This integrated approach should be applicable to directed evolution of any phage-displayed affinity reagent scaffold.