Study Report

Reference	Galimberti, D., 2014 PMID: 24499389
Citation	Galimberti, D., et al. (2014). "Progranulin gene variability influences the risk for bipolar I disorder, but not bipolar II disorder." Bipolar Disord.
Disease Type	Bipolar Disorder
Study Design	case-control
Study Type	Candidate-gene association study
Sample Size	79 BD-I and 55 BD-II patients, and 232 controls
SNP/Region/Marker Size	3 SNPs
Predominant Ethnicity	Caucasian
Population	Italian
Gender	51 male and 83 female patients, 87 male and 145 female controls; 36 male and 43 female patients with BD-I, 15 male and 40 female patients with BD-II.
Age Group	adults : mean age=51.0, SD=12.8 years of patients, range: 20~74 years; mean age=54.0, SD=15.3 years of controls, range: 24�74 years; mean age=49.0, SD=13.1 years of BD-I, range: 20�74 years; mean age=52.0, SD=12.3 years of BD-II, range: 33�74 years.

Sample Diagnosis	DSM-IV-TR
Sample Status	One hundred and thirty-four patients with BD diagnosed according to DSM-IV-TR criteria and 232 healthy age-matched controls were included in the study. Seventy-nine patients were diagnosed with BD-I and 55 with BD-II.
Technique	genotyped by allelic discrimination
Statistical Method	Allelic and genotypic frequencies were obtained by direct counting. A chi-square test was used to test for Hardy�Weinberg equilibrium (HWE) and for differences in SNP distribution between cases and controls, and BonferroniÕs correction was applied. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Progranulin plasma levels were analysed using t-tests.
Result Summary	The presence of the polymorphic variant of the rs5848 single nucleotide polymorphism is protective for the development of bipolar I disorder (BD-I) (odds ratio = 0.55, 95% confidence interval: 0.33~0.93; p = 0.024) but not bipolar II disorder (BD-II) (p > 0.05).