Now divorce is very common in our society.Divorce, also known as dissolution of marriage, is the termination of a marriage or marital union, the canceling or reorganizing of the legal duties and responsibilities of marriage, thus dissolving the bonds of matrimony between a married couple under the rule of law of the particular country or state.
It’s really nature versus nurture:when divorce runs in the family, which one is it? Is divorce passed down through generations because children spend time around their separated parents, or because parents pass on their "divorce genes?"
The past research has consistently shown that children of divorced parents are more likely to get divorced in their turn, when they reach adulthood.
According to a past study in 2004, husbands engaged in extramarital affairs in 75% of cases; wives in 25%. In cases of family strain, wives' families were the primary source of strain in 78%, compared to 22% of husbands' families.Emotional and physical abuse were more evenly split, with wives affected in 60%and husbands in 40% of cases. In 70% of workaholism-related divorces it was husbands who were the cause, and in 30%, wives. The 2004 survey found that 93%of divorce cases were petitioned by wives, very few of which were contested.53% of divorces were of marriages that had lasted 10 to 15 years, with 40%ending after 5 to 10 years. The first 5 years are relatively divorce-free, and if a marriage survives more than 20 years it is unlikely to end in divorce.
What is the reason? Is divorce transmitted across generations due to psychological and social factors - such as children tending to imitate their parents - or could there be a genetic influence at play?
Anew study, which is soon be published in the journal Psychological Science, gives more weight to the latter.
The research was carried out by scientists at the Virginia Commonwealth University (VCU) in Richmond, in collaboration with a team at Lund University in Sweden.
The first author of the study is Jessica Salvatore, Ph.D., an assistant professor in the Department of Psychology in the College of Humanities and Sciences at VCU.
Causes for divorce run in the family
Prof.Salvatore and her colleagues used so-called classical and extended adoption designs to study data available from Swedish national registries.
Speaking to Medical News Today about the methodology they used, Prof. Salvatore explained, "The basic idea with an adoption design is that it gives you a lot of traction on the question of whether something (like divorce) runs in families due to genetic and environmental factors."
"We looked at whether adoptees whose biological parents divorced were more likely to have their own marriages dissolve," she added. "We also looked at whether adoptees whose adoptive parents divorced were more likely to have their own marriages dissolve."
"If adoptees resemble their biological parents, we know that it's genetic factors that contribute to this resemblance because biological parents only give genes to their offspring," she explained.
Conversely, "If adoptees resemble their adoptive parents, we know that it's something about being raised in a divorced household that contributes to this resemblance because adoptive parents provide only an environment (not genes) to their adopted children."
In the classical adoption analyses, 19,715 adoptees - 52 percent of whom were male- had a similar divorce history as their biological parents but not their adoptive parents.
The scientists performed extended adoption analyses on 82,698 children, which revealed a significant environmental influence.
However, when the researchers tried to replicate these results "using within-generation data from adoptive and biological siblings," the results showed that "adoptees resembled their biological, but not adoptive, siblings in their history of divorce."
"Thus,"the study authors conclude, "there was consistent evidence that genetic factors contributed to the inter generational transmission divorce, but weaker evidence for a rearing environmental effect of divorce."
The study showed a different picture of divorce
Prof. Salvatore also spoke about the significance of the study, as well as its strengths and limitations. "We were surprised by the findings," she says.
"Previous studies on why divorce runs in families [...] have really focused on the pernicious effects that growing up in a divorced household has on one's own marital stability later in life. [But] in our study a different picture emerged." Prof. Jessica Salvatore
This picture, she added, suggests that "[the]reason that the offspring of divorced parents are more likely to get divorced has to do with the genes that parents and children share, rather than the experience of seeing [their] parents split up."
"A strength of this study," Prof. Salvatore told us, "is that in an adoption design, the influences of genetics and the rearing environment are disentangled from one another."
She also admits some limitations to her research, saying, "[If] biological parents and adoptees have extensive contact before the adoption, this can cause an upward bias in their resemblance."
However, as Prof. Salvatore noted, "We conducted a series of sensitivity analyses that suggested that this wasn't the case."