1. Department of Animal Science and Center for Integrated Animal Genomics; Iowa State University; 2255 Kildee Hall Ames IA 50011 USA
2. Department of Statistics; Iowa State University; 2418 Snedecor Ames IA 50011 USA
3. Animal Breeding and Genomics Centre; Wageningen University; Marijkeweg 40 Wageningen 6709 PG The Netherlands