and mRNAs Are Detectable in Human Spermatozoa.

PURPOSE

Oligozoospermia is highly prevalent worldwide. Studies have reported a lower methylation rate in the differentially methylated region at the sperm level in oligozoospermic patients than in controls. are the best-known pair of imprinted genes. However, no studies have yet evaluated whether they are transcribed in human sperm. To assess whether and mRNAs are present in human sperm and if their levels are correlated with sperm concentration and total sperm count.

MATERIALS AND METHODS

Sperm samples (n=22) underwent reverse-transcription quantitative polymerase chain reaction using specific primers to detect and mRNA levels. They were then correlated with patients' conventional sperm parameters using the Spearman (τ) and Kendall (ρ) rank correlation coefficients.

RESULTS

Statistically significant positive correlations were found between mRNA levels and sperm concentration (τ=0.403, p<0.01; ρ=0.587, p<0.005) and total sperm count (τ=0.347, p<0.024; ρ=0.509, p<0.015). mRNA levels were positively correlated with sperm concentration (τ=0.595, p<0.001; ρ=0.774, p<0.001) and total sperm count (τ=0.547, p<0.001; ρ=0.701, p<0.001). Apart from mRNA and sperm morphology (τ=0.325, p<0.05; ρ=0.461, p<0.05), no additional correlations were found between the levels of these transcripts and other conventional sperm parameters.

CONCLUSIONS

and mRNAs were found to be present in human spermatozoa and their transcription levels were positively correlated with sperm concentration and total sperm count. Spermatozoa are the only source of mRNA since is a paternally-inherited gene. Further studies are needed to evaluate its role in human fertilization.