Abstract
We report here a 28-year-old male with infertility. No abnormality was found in his semen examination. The couple achieved a successful pregnancy under the help of intracytoplasmic sperm injection during which we found that sperm could enter the zona pellucida, but could not fuse with the egg within the short insemination period. We then performed whole-exome sequencing technology on this patient and found a rare variant (c.641A>C:p.D214A) in ADAM20, which encoded a disintegrin and metalloprotease 20 protein. To further verify the pathogenicity of this variant, we analyzed ADAM20 protein expression in spermatozoa by immunostaining analysis, which showed a mis-localization of ADAM20 in the patient's spermatozoa. Therefore, we concluded that mutation in ADAM20 may be associated with sperm-egg fusion disorder in this patient.
Highlights
IntroductionSperm-egg fusion is one of the most critical events in sexual reproduction
Fertilization is a complex process involving many molecules
We report a patient with spermegg fusion disorder harbored a heterozygous ADAM20 rare variant
Summary
Sperm-egg fusion is one of the most critical events in sexual reproduction. The sperm is activated in the female reproductive tract after capacitation, resulting in modification of the membrane composition and enhancement of membrane fluidity, leading to sperm hyperactivation. Sperm will reach the cumulus, pass through layers of cumulus cells, and bind to the zona pellucida (ZP), triggering the acrosome reaction. The acrosome reaction releases a large number of enzymes that hydrolyze the local ZP such that the sperm can pass through and enter the perivitelline space. The acrosome reaction exposes the acrosome intima and alters the equatorial region and the membrane components of the post-acrosomal region [1]. Having reached the perivitelline space between the egg ZP and plasma membrane, sperm binds to and fuses with the plasma membrane at the equatorial region [2]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.