ESPE Abstracts

Introduction: Most testis expressed (TEX) genes are testis-specific and evolutionarily conserved and several studies have reported important roles of TEX11, TEX12, TEX14, TEX15 and TEX 101 in mammalian fertility. Retrotransposons are thought to be critical for the evolution of mammalian genomes. TEX19 functions in the post-translational regulation of L1 retrotransposons, which are involved in maintaining trans-generational genome stability. In boys with cryptorchidism, prepubertal hypogonadotropic hypogonadism alters expression of ASZ1, PIWIL, and CFTR. The abrogated expression of these gene leads to abnormal activation of transposons and ultimately, infertility. Here, we report TEX expression profiles in testicular biopsies from cryptorchid boys.

Patients and Methods: We sampled testicular biopsies from bilateral cryptorchid boys for histological and transcriptome analyses using the RiboMinus Gold/TrueSeq (Illumina) RNA-Sequencing protocol. Lacking Ad spermatogonia distinguished high infertility risk (HIR) from low infertility risk (LIR) patients. HIR patients were randomized for treatment either with surgery and GnRHa or surgery only.

Results: 10 TEX genes were expressed at lower levels in samples from HIR patients as compared to low infertility risk controls (Table 1). Following GnRHa treatment, we identified three TEX genes, TEX19, involved in retrotransposon control, TEX35 in Leydig cell development and TEX38 important for spermatogenesis, that showed increased expression signals (Table 1).

Conclusion We report novel testicular TEX expression profiles in cryptorchid patients, and their response to GnRHa treatment. We found that curative GnRHa treatment stimulates TEX19 expression, which might contribute to silencing of retrotransposons. Our data are consistent with TEX11’s previous association with azoospermia.