In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

[EX Q]: Context: The PlA1/A2 polymorphism of platelet glycoprotein IIIa (GPIIIa) has been implicated in the pathogenesis of type 2 diabetes. We studied this polymorphism in a homogenous, extensively phenotyped cohort using the candidate gene approach.', 'The PlA1/A2 polymorphism was determined in 1051 patients with type 2 diabetes and in 2247 individuals without type 2 diabetes.', 'In patients with type 2 diabetes, genotype frequencies were as follows: PlA1/A1 71.4%, PlA1/A2 26.0%, and PlA2/A2 2.7%. In individuals without type 2 diabetes, genotype frequencies were 71.6%, 25.7% and 2.8%, respectively. The PlA2 allele was not associated with fasting and postprandial glucose, glycated haemoglobin, insulin, proinsulin, C-peptide and calculated indices of insulin resistance or pancreatic beta cell function. The PlA2 allele was also not significantly associated with angiographic CHD (adjusted odds ratio [OR] 1.13; 95% CI, 0.93-1.39) or with a history of previous myocardial infarction (adjusted OR 1.09; 95% CI, 0.87-1.37).\Question: Is the PlA1/A2 polymorphism of platelet glycoprotein IIIa associated with the risk of type 2 diabetes . The Ludwigshafen Risk and Cardiovascular Health study?
[EX A]: The GPIIIa PlA1/A2 polymorphism is not associated with type 2 diabetes, glucose metabolism, angiographic CHD or myocardial infarction.

[EX Q]: Context: Collagenous colitis (CC) is a major cause of chronic non-bloody diarrhoea, particularly in the elderly female population. The aetiology of CC is unknown, and still poor is the understanding of its pathogenesis. This possibly involves dysregulated inflammation and immune-mediated reactions in genetically predisposed individuals, but the contribution of genetic factors to CC is underinvestigated. We systematically tested immune-related genes known to impact the risk of several autoimmune diseases for their potential CC-predisposing role.', 'Three independent cohorts of histologically confirmed CC cases (N=314) and controls (N=4299) from Sweden and Germany were included in a 2-step association analysis. Immunochip and targeted single nucleotide polymorphism (SNP) genotype data were produced, respectively, for discovery and replication purposes. Classical human leucocyte antigen (HLA) variants at 2-digit and 4-digit resolution were obtained via imputation from single marker genotypes. SNPs and HLA variants passing quality control filters were tested for association with CC with logistic regression adjusting for age, sex and country of origin.', 'Forty-two markers gave rise to genome-wide significant association signals, all contained within the HLA region on chromosome 6 (best p=4.2×10\Question: Does dense genotyping of immune-related loci identify HLA variants associated with increased risk of collagenous colitis?
[EX A]: HLA genotype associates with CC, thus implicating HLA-related immune mechanisms in its pathogenesis.

[EX Q]: Context: The initiation of an action potential by extracellular stimulation occurs after local depolarization of the neuronal membrane above threshold. Although the technique shows remarkable clinical success, the site of action and the relevant stimulation parameters are not completely understood.', 'Here we identify the site of action potential initiation in rabbit retinal ganglion cells (RGCs) interfaced to an array of extracellular capacitive stimulation electrodes. We determine which feature of the extracellular potential governs action potential initiation by simultaneous stimulation and recording RGCs interfaced in epiretinal configuration. Stimulation electrodes were combined to areas of different size and were presented at different positions with respect to the RGC.', 'Based on stimulation by electrodes beneath the RGC soma and simultaneous sub-millisecond latency measurement we infer axonal initiation at the site of maximal curvature of the extracellular potential. Stimulation by electrodes at different positions along the axon reveals a nearly constant threshold current density except for a narrow region close to the cell soma. These findings are explained by the concept of the activating function modified to consider a region of lower excitability close to the cell soma.\Question: Are action potentials in retinal ganglion cells initiated at the site of maximal curvature of the extracellular potential?
[EX A]:
We present a framework how to estimate the site of action potential initiation and the stimulus required to cross threshold in neurons tightly interfaced to capacitive stimulation electrodes. Our results underscore the necessity of rigorous electrical characterization of the stimulation electrodes and of the interfaced neural tissue.