ZN conducted the genetic studies, participated in the study design, and drafted the manuscript. KLR and GF participated in the study design and acquisition of data in the US and Hungarian site, respectively. AS and EB participated in the analyses of the Hungarian and the US study, respectively. KLR, AS and MSS helped in revising the manuscript. MSS conceived of both genetic studies, and participated in design and coordination. All authors read and approved the final manuscript.
