Dionisios Sakkas, PhD
Research & Publications
Biography
Research Summary
Spermatogenesis is a complex process leading to the production of a
haploid cell that possesses a nucleus that is up to 1/40th the size of
a normal somatic cell. In the human the process is not always foolproof
and abnormal semen parameters remains as one of the most common causes
of sub-fertility amongst couples. In the human, a strong association
has been found between abnormal semen parameters and the presence of
nuclear DNA strand breaks in ejaculated sperm. Two likely mechanisms
that could function abnormally and be responsible for the DNA strand
breaks are the disruption of ordered testicular apoptosis during
spermatogenesis, in particular the Fas mediated pathway, and / or the
faulty remodeling of the DNA during spermiogenesis. The purpose of our
work is to understand how these mechanisms function during normal
spermatogenesis and how they impact on male infertility. Furthermore,
we are interested in the role an abnormal paternal genome may play if
it successfully fertilizes an oocyte.
Selected Publications
- Abnormal sperm parameters in humans are indicative of an abortive apoptotic mechanism linked to the Fas-mediated pathway.Sakkas D, Mariethoz E, St John JC. Abnormal sperm parameters in humans are indicative of an abortive apoptotic mechanism linked to the Fas-mediated pathway. Experimental Cell Research 1999, 251: 350-5. PMID: 10471320, DOI: 10.1006/excr.1999.4586.
- Origin of DNA damage in ejaculated human spermatozoa.Sakkas D, Mariethoz E, Manicardi G, Bizzaro D, Bianchi PG, Bianchi U. Origin of DNA damage in ejaculated human spermatozoa. Reviews Of Reproduction 1999, 4: 31-7. PMID: 10051100.