Mapping the past, present and future research landscape of paternal effects

BACKGROUND

Although in all sexually reproducing organisms an individual has a mother and a father, non-genetic inheritance has been predominantly studied in mothers. Paternal effects have been far less frequently studied, until recently. In the last 5 years, research on environmentally induced paternal effects has grown rapidly in the number of publications and diversity of topics. Here, we provide an overview of this field using synthesis of evidence (systematic map) and influence (bibliometric analyses).

RESULTS

We find that motivations for studies into paternal effects are diverse. For example, from the ecological and evolutionary perspective, paternal effects are of interest as facilitators of response to environmental change and mediators of extended heredity. Medical researchers track how paternal pre-fertilization exposures to factors, such as diet or trauma, influence offspring health. Toxicologists look at the effects of toxins. We compare how these three research guilds design experiments in relation to objects of their studies: fathers, mothers and offspring. We highlight examples of research gaps, which, in turn, lead to future avenues of research.

CONCLUSIONS

The literature on paternal effects is large and disparate. Our study helps in fostering connections between areas of knowledge that develop in parallel, but which could benefit from the lateral transfer of concepts and methods.

Outcomes of Pregnancies Fathered by Solid-Organ Transplant Recipients Exposed to Mycophenolic Acid Products

Context

In women, exposure to mycophenolic acid products during pregnancy results in an increase in both miscarriages and birth defects in the live born.

Objective

To describe the outcomes of pregnancies fathered by transplant recipients who were being maintained on mycophenolic acid products at the estimated time of conception and compare these pregnancies with pregnancies in the general population.

Methods

Data were collected by the National Transplantation Pregnancy Registry via questionnaires, telephone interviews, and medical records.

Results

One hundred fifty-two male transplant recipients with exposure to mycophenolic acid products fathered 205 pregnancies (208 outcomes, including 3 pairs of twins). Pregnancy outcomes included 194 live births with a prematurity rate of 10.8%, 14 spontaneous abortions, and no therapeutic abortions or stillbirths. Among the live births, 6 malformations were reported, for an incidence of 3.1%. No pattern of malformations was identified.

Conclusion

The outcomes of pregnancies fathered by transplant recipients treated with mycophenolic acid products appear similar to outcomes in the general population.