Replicating a GWAS: two novel candidate markers for oligospermia in Greek population.

Genome-wide association studies have paved the way for the discovery of new markers regarding many diseases, including male infertility. A previous study on Caucasians highlighted 172 polymorphisms for their putative association with male infertility and we attempted to replicate these findings on our dataset comprising of Greek male individuals (n = 360). We retrieved 59 out of 172 polymorphisms and tested for all association models on 278 normospermic men and 82 patients with an abnormal seminogram, later separated into oligozoospermic and asthenozoospermic groups. Our findings indicate that two SNPs (rs2296225 in KIF17, rs7224496 in SMYD4) are associated with male infertility in the Greek population and have not been recorded in literature as of yet. These novel markers need further validation via additional studies and an increased individual number. All in all, replication studies, possess the power to validate existing polymorphisms found across all population and thus increase both statistical significance as well as identify novel potentially diagnostic markers.

Genome-wide association study identifies candidate markers related to lincRNAs associated with male infertility in the Greek population.

BACKGROUND: Male infertility is currently one of the most common problems faced by couples worldwide. We performed a GWAS on Greek population and gathered statistically significant SNPs in order to investigate whether they lie within or near lncRNA regions. OBJECTIVES: The aim of this study was to investigate whether polymorphisms on or near lncRNAs affect interactions with miRNAs and can cause male infertility. MATERIALS AND METHODS: In the present study, a GWAS was conducted, using samples from 159 individuals (83 normozoospermic individuals and 76 patients of known fertility issues). Standard procedures for quality controls and association testing were followed, based on case-control testing. RESULTS: We detected six lncRNAs (LINC02231, LINC00347, LINC02134, NCRNA00157, LINC02493, Lnc-CASK-1) that are associated with male infertility through their interaction with miRNAs. Furthermore, we identified the genes targeted by those miRNAs and highlighted their functions in spermatogenesis and the fertilization process. DISCUSSION AND CONCLUSION: lncRNAs are involved in spermatogenesis through their interaction with miRNAs. Thus, their study is very important, and it may contribute to the understanding of the molecular mechanisms underlying male infertility.

Male infertility and the impact of lifestyle in the Greek population: A case-control study.

Background and Aims: Collection of epidemiological data has become a crucial step in every fertility evaluation, especially regarding idiopathic male infertility. Information on data such as tobacco smoking, alcohol intake, and body mass index can provide crucial information regarding the dynamics between fertility status and everyday practices. We aim to set the base for epidemiological studies on male infertility in the Greek population. Methods: Four hundred and fourteen Greek volunteers were asked to fill in a questionnaire regarding their characteristics and lifestyle preferences, followed by a seminogram. Depending on their answers, they were divided into groups and data were analyzed for correlation with seminogram parameters using Spearman's rank correlation test. Results: Our results indicate that a high body mass index (BMI) is negatively correlated with all three seminogram parameters (number, motility, and morphology) and exposure to radiation or chemicals is negatively correlated with sperm motility, with a p < 0.01. Conclusions: These findings indicate negative correlations of BMI and exposure to radiation/chemicals with semen parameters in the Greek population. Such information can be used to plan a diagnostic approach or even therapeutic interventions.