A single-cell assay for telomere DNA content shows increasing telomere length heterogeneity, as well as increasing mean telomere length in human spermatozoa with advancing age

• Published in: Journal of assisted reproduction and genetics Vol. 32; no. 11; pp. 1685 - 1690
• Main Authors: Antunes, Danielle M. F., Kalmbach, Keri H., Wang, Fang, Dracxler, Roberta C., Seth-Smith, Michelle L., Kramer, Yael, Buldo-Licciardi, Julia, Kohlrausch, Fabiana B., Keefe, David L.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.11.2015; Springer Nature B.V
• Subjects: Adult; Age; Cell division; Chromosomes; Cross-Sectional Studies; DNA - analysis; Fertility; Gynecology; Homeostasis; Human Genetics; Humans; In vitro fertilization; Infertility; Male; Medicine; Medicine & Public Health; Middle Aged; Morphology; Obstetrics; Paternal Age; Prospective Studies; Reproductive Medicine; Senescence; Single-Cell Analysis - methods; Sperm; Spermatogenesis; Spermatozoa - physiology; Stem cells; Technological Innovations; Telomerase; Telomere - genetics; Telomere Homeostasis - genetics; Yeast; New York; United States > US; In vitro fertilization; Telomeres; Paternal age; Sperm morphology; Human spermatozoa
• ISSN: 1058-0468; 1573-7330
• DOI: 10.1007/s10815-015-0574-3

Purpose The effect of age on telomere length heterogeneity in men has not been studied previously. Our aims were to determine the relationship between variation in sperm telomere length (STL), men’s age, and semen parameters in spermatozoa from men undergoing in vitro fertilization (IVF) treatment. Methods To perform this prospective cross-sectional pilot study, telomere length was estimated in 200 individual spermatozoa from men undergoing IVF treatment at the NYU Fertility Center. A novel single-cell telomere content assay (SCT-pqPCR) measured telomere length in individual spermatozoa. Results Telomere length among individual spermatozoa within an ejaculate varies markedly and increases with age. Older men not only have longer STL but also have more variable STL compared to younger men. STL from samples with normal semen parameters was significantly longer than that from samples with abnormal parameters, but STL did not differ between spermatozoa with normal versus abnormal morphology. Conclusion The marked increase in STL heterogeneity as men age is consistent with a role for ALT during spermatogenesis. No data have yet reported the effect of age on STL heterogeneity. Based on these results, future studies should expand this modest sample size to search for molecular evidence of ALT in human testes during spermatogenesis.