Concept: Paternal bond
While many studies have shown that maternal weight and nutrition in pregnancy affects offspring’s breast cancer risk, no studies have investigated the impact of paternal body weight on daughters' risk of this disease. Here, we show that diet-induced paternal overweight around the time of conception can epigenetically reprogram father’s germ-line and modulate their daughters' birth weight and likelihood of developing breast cancer, using a mouse model. Increased body weight was associated with changes in the miRNA expression profile in paternal sperm. Daughters of overweight fathers had higher rates of carcinogen-induced mammary tumors which were associated with delayed mammary gland development and alterations in mammary miRNA expression. The hypoxia signaling pathway, targeted by miRNAs down-regulated in daughters of overweight fathers, was activated in their mammary tissues and tumors. This study provides evidence that paternal peri-conceptional body weight may affect daughters' mammary development and breast cancer risk and warrants further studies in other animal models and humans.
- Proceedings of the National Academy of Sciences of the United States of America
- Published over 6 years ago
Although contemporary socio-cultural changes dramatically increased fathers' involvement in childrearing, little is known about the brain basis of human fatherhood, its comparability with the maternal brain, and its sensitivity to caregiving experiences. We measured parental brain response to infant stimuli using functional MRI, oxytocin, and parenting behavior in three groups of parents (n = 89) raising their firstborn infant: heterosexual primary-caregiving mothers (PC-Mothers), heterosexual secondary-caregiving fathers (SC-Fathers), and primary-caregiving homosexual fathers (PC-Fathers) rearing infants without maternal involvement. Results revealed that parenting implemented a global “parental caregiving” neural network, mainly consistent across parents, which integrated functioning of two systems: the emotional processing network including subcortical and paralimbic structures associated with vigilance, salience, reward, and motivation, and mentalizing network involving frontopolar-medial-prefrontal and temporo-parietal circuits implicated in social understanding and cognitive empathy. These networks work in concert to imbue infant care with emotional salience, attune with the infant state, and plan adequate parenting. PC-Mothers showed greater activation in emotion processing structures, correlated with oxytocin and parent-infant synchrony, whereas SC-Fathers displayed greater activation in cortical circuits, associated with oxytocin and parenting. PC-Fathers exhibited high amygdala activation similar to PC-Mothers, alongside high activation of superior temporal sulcus (STS) comparable to SC-Fathers, and functional connectivity between amygdala and STS. Among all fathers, time spent in direct childcare was linked with the degree of amygdala-STS connectivity. Findings underscore the common neural basis of maternal and paternal care, chart brain-hormone-behavior pathways that support parenthood, and specify mechanisms of brain malleability with caregiving experiences in human fathers.
This study used cross-lagged modeling to examine reciprocal relations between maternal and paternal harsh verbal discipline and adolescents' conduct problems and depressive symptoms. Data were from a sample of 976 two-parent families and their children (51% males; 54% European American, 40% African American). Mothers' and fathers' harsh verbal discipline at age 13 predicted an increase in adolescent conduct problems and depressive symptoms between ages 13 and 14. A child effect was also present, with adolescent misconduct at age 13 predicting increases in mothers' and fathers' harsh verbal discipline between ages 13 and 14. Furthermore, maternal and paternal warmth did not moderate the longitudinal associations between mothers' and fathers' use of harsh verbal discipline and adolescent conduct problems and depressive symptoms.
OBJECTIVE:To examine the prevalence of maternal and paternal spanking of children at 3 and 5 years of age and the associations between spanking and children’s externalizing behavior and receptive vocabulary through age 9.METHODS:The Fragile Families and Child Well-Being Study, a longitudinal birth cohort study of children in 20 medium to large US cities, was used. Parental reports of spanking were assessed at age 3 and 5, along with child externalizing behavior and receptive vocabulary at age 9 (N = 1933). The data set also included an extensive set of child and family controls (including earlier measures of the child outcomes).RESULTS:Overall, 57% of mothers and 40% of fathers engaged in spanking when children were age 3, and 52% of mothers and 33% of fathers engaged in spanking at age 5. Maternal spanking at age 5, even at low levels, was associated with higher levels of child externalizing behavior at age 9, even after an array of risks and earlier child behavior were controlled for. Father’s high-frequency spanking at age 5 was associated with lower child receptive vocabulary scores at age 9.CONCLUSIONS:Spanking remains a typical rearing experience for American children. These results demonstrate negative effects of spanking on child behavioral and cognitive development in a longitudinal sample from birth through 9 years of age.
Prenatal hormones in first-time expectant parents: Longitudinal changes and within-couple correlations
- American journal of human biology : the official journal of the Human Biology Council
- Published about 6 years ago
Expectant mothers experience marked hormone changes throughout the transition to parenthood. Although similar neuroendocrine pathways are thought to support maternal and paternal behavior, much less is known about prenatal hormone changes in expectant fathers, especially in humans.
Positive father involvement is associated with positive child outcomes. There is great variation in fathers' involvement and fathering behaviors, and men’s testosterone (T) has been proposed as a potential biological contributor to paternal involvement. Previous studies investigating testosterone changes in response to father-infant interactions or exposure to infant cues were unclear as to whether individual variation in T is predictive of fathering behavior. We show that individual variation in fathers' T reactivity to their infants during a challenging laboratory paradigm (Strange Situation) uniquely predicted fathers' positive parenting behaviors during a subsequent father-infant interaction, in addition to other psychosocial determinants of paternal involvement, such as dispositional empathy and marital quality. The findings have implications for understanding fathering behaviors and how fathers can contribute to their children’s socioemotional development. © 2015 Wiley Periodicals, Inc. Dev Psychobiol.
Rates of paternal depression range from 5% to 10% with a growing body of literature describing the harm to fathers, children, and families. Changes in depression symptoms over the life course, and the role of social factors, are not well known. This study examines associations with changes in depression symptoms during the transition to fatherhood for young fathers and whether this association differed by key social factors.
Following the birth of an infant, decreases in testosterone and increases in depressive symptoms have been observed in fathers. Paternal testosterone may reflect fathers' investment in pair-bonding and paternal caregiving and, as such, may be associated with maternal and familial well-being. This study tests associations between paternal testosterone, paternal and maternal postpartum depressive symptoms, and subsequent family functioning. Within 149 couples, fathers provided testosterone samples when infants were approximately nine months old and both parents reported on postpartum depressive symptoms at two, nine, and 15months postpartum. Fathers with lower aggregate testosterone reported more depressive symptoms at two and nine months postpartum. Mothers whose partners had higher evening testosterone reported more depressive symptoms at nine and 15months postpartum. Maternal relationship satisfaction mediated this effect, such that mothers with higher testosterone partners reported more relationship dissatisfaction, which in turn predicted more maternal depressive symptoms. Higher paternal testosterone and paternal depressive symptoms at nine months postpartum each independently predicted greater fathering stress at 15months postpartum. Higher paternal testosterone also predicted more mother-reported intimate partner aggression at 15months postpartum. In addition to linear relationships between testosterone and depression, curvilinear relationships emerged such that fathers with both low and high testosterone at nine months postpartum reported more subsequent (15-month) depressive symptoms and fathering stress. In conclusion, whereas higher paternal testosterone may protect against paternal depression, it contributed to maternal distress and suboptimal family outcomes in our sample. Interventions that supplement or alter men’s testosterone may have unintended consequences for family well-being.
De novo mutations (DNMs) originating in gametogenesis are an important source of genetic variation. We use a data set of 7,216 autosomal DNMs with resolved parent of origin from whole-genome sequencing of 816 parent-offspring trios to investigate differences between maternally and paternally derived DNMs and study the underlying mutational mechanisms. Our results show that the number of DNMs in offspring increases not only with paternal age, but also with maternal age, and that some genome regions show enrichment for maternally derived DNMs. We identify parent-of-origin-specific mutation signatures that become more pronounced with increased parental age, pointing to different mutational mechanisms in spermatogenesis and oogenesis. Moreover, we find DNMs that are spatially clustered to have a unique mutational signature with no significant differences between parental alleles, suggesting a different mutational mechanism. Our findings provide insights into the molecular mechanisms that underlie mutagenesis and are relevant to disease and evolution in humans.
Increasing evidence suggests that postnatal paternal depression is associated with adverse emotional, behavioural and cognitive outcomes in children. Despite this, few studies have determined the prevalence of fathers' depressive symptoms during the first few years of their children’s lives and explored what factors are related to these symptoms. We estimated the prevalence and examined associated risk factors of paternal depressive symptoms in a nationally representative sample of fathers with children aged between 9 months and 7 years old from the Millennium cohort study. The risk factors examined were maternal depressive symptoms, marital conflict, child temperament, child gender, paternal education, fathers' ethnic background, fathers' employment status, family housing, family income and paternal age.