Developmental sperm contributions: fertilization and beyond.
The objective of this review was to examine the role of the various spermatozoal components suspected of actively participating in early human development. The contributions of the fertilizing spermatozoon to the oocyte include, as a minimum, the delivery of the DNA/chromatin, a putative oocyte-activating factor (OAF), and a centriole. Recent data indicate that spermatozoa may also provide the zygote with a unique suite of paternal mRNAs; some transcripts might be crucial for early and late embryonic development and deficient delivery, or aberrant transcription might contribute to abnormal development and arrest. Clinical evidence from assisted reproduction suggests that failure to complete the fertilization process, syngamy, or early cleavage might be the result of an early paternal effect. It is speculated that an abnormal release of a putative OAF and/or dysfunctions of the centrosome and cytoskeletal apparatus may mediate these effects. On the other hand, a later paternal effect resulting in embryonic failure to achieve implantation, pregnancy loss, and/or developmental abnormalities resulting from "carried over" sublethal effects may be associated with sperm nuclear/chromatin defects, including the presence of aneuploidy, genetic anomalies, DNA damage, and possibly other causes. These findings highlight the need for continuous monitoring of clinical results.
Barroso
Gerardo
G
Reproductive Medicine and Infertility Division, National Institute of Perinatology, Mexico City, Mexico. Electronic address: asistida@servidor.inper.edu.mx.
Valdespin
Carlos
C
Reproductive Medicine and Infertility Division, National Institute of Perinatology, Mexico City, Mexico.
Vega
Eva
E
Reproductive Medicine and Infertility Division, National Institute of Perinatology, Mexico City, Mexico.
Kershenovich
Ruben
R
Reproductive Medicine and Infertility Division, National Institute of Perinatology, Mexico City, Mexico.
Avila
Rosaura
R
Reproductive Medicine and Infertility Division, National Institute of Perinatology, Mexico City, Mexico.
Avendaño
Conrado
C
Obstetrics and Gynecology Department, Jones Institute for Reproductive Medicine, Eastern Virginia Medical School, Norfolk, Virginia.
Oehninger
Sergio
S
Obstetrics and Gynecology Department, Jones Institute for Reproductive Medicine, Eastern Virginia Medical School, Norfolk, Virginia.
D000818:Animals; D002502:Centrioles / Q000502:physiology; D004272:DNA, Mitochondrial / Q000502:physiology; D047108:Embryonic Development / Q000502:physiology*; D005260:Female; D005306:Fertilization / Q000502:physiology*; D006801:Humans; D008297:Male; D027724:Reproductive Techniques, Assisted; D013084:Sperm-Ovum Interactions / Q000502:physiology; D013094:Spermatozoa / Q000502:physiology*
D004272:DNA, Mitochondrial