Long-Term Effects Following Fresh/Vitrified Embryo Transfer Are Transmitted by Paternal Germline in a Large Size...

Area of Science:

• Reproductive Biology
• Developmental Biology
• Epigenetics

Background:

• Assisted reproductive technologies (ARTs) can disrupt the optimal maternal environment for embryos.
• In vitro manipulations during embryo transfer are linked to developmental deviations in offspring.
• Previous research indicated cumulative and transgenerational declines in growth performance following vitrified embryo transfer.

Purpose of the Study:

• To investigate the paternal versus maternal transmission of developmental deviations induced by early embryo manipulations.
• To determine if fresh or vitrified embryo transfer procedures differentially affect transgenerational inheritance of growth patterns.
• To elucidate the primary trigger for transmissible effects: in vitro manipulation or cryopreservation.

Main Methods:

• Longitudinal study design utilizing crossbred matings.
• Comparison of offspring from fresh embryo transfer versus vitrified embryo transfer procedures.
• Assessment of growth performance and adult body weight across generations.

Main Results:

• Early embryo manipulations via both fresh and vitrified embryo transfer induced paternally transmissible effects on growth patterns and adult body weight.
• These effects did not appear to be inherited through the female germline.
• Similar inheritable effects were observed regardless of whether fresh or vitrified embryo transfer was used.

Conclusions:

• In vitro manipulation of embryos during assisted reproductive technologies is the principal trigger for transmissible developmental effects.
• Paternal germline transmission is implicated in the inheritance of growth and body weight deviations following ART.
• Embryo cryopreservation per se is not the primary cause of these long-term, transgenerational effects.