Does detection of DDX4 mRNA in cell‐free seminal plasma represents a reliable noninvasive germ cell marker in patients with nonobstructive azoospermia?

Summary This study aimed to investigate the potential application of DDX4 gene expression in cell‐free seminal mRNA as a noninvasive biomarker for the identification of the presence of germ cells in men with nonobstructive azoospermia and to correlate this factor with testicular biopsy. Male reproductive organ‐specific genes were chosen: DDX4, which is a germ cell‐specific gene and transglutaminase 4, which is a prostate‐specific gene that was used as a control gene. Thirty‐nine azoospermic males and twenty‐eight normospermic fertile males (serving as a control group) participated in the study. Histopathological examination of testicular biopsies categorised azoospermic males into 20.5% with maturation arrest, 17.9% with incomplete Sertoli cell‐only syndrome and 61.5% with complete Sertoli cell‐only syndrome. Using real‐time polymerase chain reaction, positivity for DDX4 gene was detected in 17 of 39 males with NOA which was due to maturation arrest in 35.3% (n = 6/17) of cases, due to incomplete Sertoli cell only in 23.5% (n = 4/17) and due to complete Sertoli cell only in 41.2% (n = 7/17). The study recommends joint utilisation of molecular transcripts as noninvasive biomarkers and histopathological examination of testicular biopsies in management of cases with azoospermia of the nonobstructive type.