Abstract: Fertility problems affect (1 in 10) couples in Western society, making it one of the most common serious health issues. Despite this, little is known about the causes of infertility, and thus patient counseling and treatment are suboptimal. With infertility being such a common problem, identification of any cause would impact on a large number of patients, allowing better counseling, clearer diagnoses and the possibility of making more informed choices (e.g. adoption vs. IVF treatment). The present invention provides methods to identify a cause of infertility in a subject based on the genotype of the subject, in particular, by evaluating the status of the gene encoding FK506 binding protein-like (FKBPL). In particular, the present invention relates to use of the status of the gene encoding FK506 binding protein-like for identification of a cause of an infertile phenotype in a subject.

Abstract: The present invention provides a method for producing a transgenic (Tg) non-human animal capable of developing an enhanced humoral immune response against an antigen as compared to a non-transgenic control animal of the same species, comprising introducing into said non-human animal a genetic construct providing for enhanced MHC class I-related neonatal Fc receptor (FcRn) activity. Also provided a Tg non-human animal comprising a genetic construct providing for enhanced FcRn activity, as well as the use of such animal in a non-therapeutical method. Therapeutic genetic constructs and methods are also provided. The present invention further provides methods for producing immunoglobulins.