Epigenetic Integrity of Spermatozoa in Patients With Germinal Testicular Tumours

Recent data suggest that sperm cells carry an epigenetic message during spermatogenesis and that this message is crucial for the future development of the embryo. This epigenetic signature is notably represented by methylation of genes subjected to imprinting (GSI) and the methylation of transposable elements (TE). Data on the maintenance of the imprint and of the control of TE accompanying human gametogenesis in a context of adult germinal testicular cancers, seminomas, are extremely fragmentary for tumour tissues and inexistent for gametes. The aim of this study is to determine whether patients with seminomas in comparison with fertile men carry a higher risk of presenting epigenetic alterations affecting their gametes. This study is based on the use of an existing collection of biological samples. 90 samples will be selected and split into 3 groups: * Group 1: 30 sperm samples from patients with seminomatous testicular tumours * Group 2: 30 sperm samples from fertile patients * Group 3: 30 sperm samples from infertile patients After treatment of the samples (thawing, cell sorting and removal of cryoprotectants), they will be analysed.