The role of telomeres in male infertility
Infertility has become one of the 21st century’s growing social problems. Numerous studies suggest that between 8-12% of couples are infertile – this meaning that women cannot achieve pregnancy when trying to conceive for a year or even longer. Infertility affects an estimated 15% of couples globally. Out of all infertility cases, the male factor alone represents around 30%, while the other 30% is due to a combination of male and female factors.
What are the main causes of male infertility?
There are multiple reasons for male infertility which can be generally categorized into 3 groups:
Medical causes are those male fertility problems arising from health issues such as varicocele, infection, hormone imbalance, tumors, ejaculation problems, chromosomal defects, celiac disease, prior surgeries etc.
Environmental causes are at time to blame when the individuals are overexposed to nocive ambient factors including chemicals, heat and toxins that can lead to a reduction in sperm function and production.
Finally, overall health, lifestyle or other causes can be the source of the problem including alcohol and illicit drug use, tobacco smoking, stress and weight.
Many of these can be considered as risk factors leading to infertility, however, it is believed that the primary factor and the most common cause of male infertility is a low sperm count as a result of an elevated temperature in the testicles.
Due to the large number of risk factors a doctor would usually recommend a battery of tests and diagnostic procedures such as a general physical examination, medical history review and semen analysis. Depending on the results, additional tests may be suggested too. In many cases seminological parameters however are not sufficient to explain the causes of male infertility. This is because the effectiveness of semen analysis is somewhat limited in terms of predicting whether a man is fertile or not as this technique often fails to identify semen abnormalities. This has prompted a search for new techniques and markers with better clinical applications. The results of some of the completed and ongoing studies indicate that the assessment of sperm telomere length is one of this new, promising male infertility markers.
What is the relationship? Could it be a causal effect? Since telomeres are necessary to complete embryogenesis, they have been the investigated as potential cause to explain male infertility, especially in those cases when is the root cause of infertility is unknown.
Telomere assessment in sperm can be done using various technologies such as TRF, Q-PCR, Flow cytometry and HT- Q-FISH in interphase (such as TAT®). The last one has the advantage of measuring chromosome ends individually and providing the whole distribution of the resulting lengths that can, in turn, be use for a thorough analysis of sperm health status.
There is undoubtedly a correlation between sperm telomere length and abnormal sperm parameters and both, sperm and ova shortened telomere may limit the successful growth of embryos. The actual role of telomeres in male infertility requires further investigations to grant the application and utility of telomeres in the field of infertility.
If you want to know more about telomeres and telomere testing please visit www.lifelength.com.