Project description:Male factor infertility affects about 7% of men in the general population and it can be related to a number of different etiologic factors, including genetic anomalies. Both sex chromosomes are enriched in genes prevalently or exclusively expressed in the testis. Nevertheless only the Y chromosome-linked Copy Number Variants (CNVs) and Y-linked genes have been demonstrated as important contributors to impaired sperm production in humans Data on the potential role of X-linked gene products in spermatogenesis derives mainly from model organisms. X-linked genes seem to be expressed both in pre-meiotic and post-meiotic germ cells in the mouse testis and interestingly those expressed in the post-meiotic cells belong to multicopy gene families. The apparent paucity of X-linked factors in male infertility is most likely related to the scarcity of studies, which focused only on a total of seven genes. No pathogenic mutations causing infertility have, thus far, been described in these genes, with the exception of AR gene In order to advance in the understanding of the role of X-linked CNVs and genes in male infertility, we applied an innovative approach based on high resolution X chromosome specific CGH array. Given that such a detailed analysis of the X chromosome has not been published so far and the testicular function of subjects included in the Genomic Variant Database is unknown (except for 24 X-linked CNVs reported in the recent paper by Tuttelmann), our is the first study providing a detailed analysis of X-linked losses and gains in several hundreds of subjects with known sperm parameters.
Project description:Male factor infertility is increasing and recognized as playing a key role in reproductive health and disease. The current primary diagnostic approach is to assess sperm quality associated with reduced sperm number and motility, which has been historically of limited success in separating fertile from infertile males. The current study was designed to develop a molecular analysis to identify male infertility using genome wide alterations in sperm DNA methylation. A signature of differential DNA methylation regions (DMRs) was identified to be associated with male infertility patients. A promising therapeutic treatment of male infertility is the use of follicle stimulating hormone (FSH) analogs which improved sperm numbers and motility in a sub-population of infertility patients. The current study also identified genome-wide DMRs that were associated with the patients that were responsive to FSH therapy versus those that were non-responsive.