OUR FIRST EXPERIENCE WITH THE COMET ASSAY IN THE STUDY OF SPERM DNA INTEGRITY

Česká verzia

Authors: Božena Novotná ¹; Lucie Svobodová ²; Marcela Čechová ³; Ladislav Jarolím ³; Matúš Chocholatý ³; Yana Bagryantseva ¹; Sr. Milan Macek ²; Milan Macek jr. ²
Authors place of work: Ústav experimentální medicíny v. v. i., AV ČR, Praha ¹; Ústav biologie a lékařské genetiky 2. LF UK a FN Motol, Praha ²; Urologická klinika 2. LF UK a FN Motol, Praha ³
Published in the journal: Ces Urol 2016; 20(4): 317-325
Category: Original Articles

Summary

Major statement:
Based on published data, the authors highlight the importance of assessment of sperm DNA integrity in the investigation of causes of infertility. Information is complemented by our own experimental results obtained by comet assay and commercial kit Halosperm.

Aim:
Abnormalities in chromatin arrangement and/or structure of the sperm DNA can significantly reduce the fertilizing potential of individuals, even in cases with normal results of conventional sperm analysis. Therefore, evaluation of sperm DNA integrity is currently emphasized in identifying the causes of male infertility. For this purpose, we decided to use comet assay and a commercially available test Halosperm with the aim to compare the two methods in the investigation of control subjects and patients with fertility disorders.

Patients and Methods:
Conventional semen analysis was performed in 32 control subjects, 24 men with infertility and 26 men with vascular disorders of male genital organs, and then the levels of DNA fragmentation in the sperm were examined using the comet assay and Halosperm.

Results:
Correlation analysis confirmed good agreement between the results of both methods (Pearson coeficient r = 0.241; p < 0.05); unlike the comet assay, the results of Halosperm correlated well with sperm motility (r = 0.4365; p < 0.001). While comet assay showed significantly higher sperm DNA damage in both groups of patients than in the controls (t-test, both p < 0.001), Halosperm demonstrated increased levels of fragmented DNA over control values only in the group of men with infertility (p < 0.001). From the results of comet assay in the control group, 32% of fragmented DNA per sperm was determined as the upper limit of the tolerance interval indicating a reduced fertilizing potential.

Conclusion:
The comet assay has proven to be a useful complementary method to the standard examination of sperm quality.

Key words:
Comet assay, DNA fragmentation, Halosperm, infertility, sperm.

Zdroje

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