The research showed five distinct genetic data points which appear common among individuals who reported at least one same-sex encounter. Two of these markers appear linked to hormones and smell, factors in sexual attraction.
But the five markers together explained less than 1% of differences in sexual activity among the population, the results found.
"Although they did find particular genetic loci associated with same-sex behavior," Mills said, "when they combine the effects of these loci together into one comprehensive score, the effects are so small, under 1%, that this genetic score cannot in any way be used to predict same-sex sexual behavior of an individual."
Noting that the study results highlight considerable differences by generation and the influence of cultural norms on sexual behavior, Mills concluded that future research was best focused on "how genetic predispositions are altered by environmental factors."
"Once again it's also important that we listen to the lived experience of LGBT people, as we minister to them in the church," Martin said.
Dr. Kevin Miller, assistant professor of theology at Franciscan University in Steubenville, Ohio, told CNA that the results are in accord with the Church's existing teaching about homosexualtiy.
"The Catechism treats homosexuality in nos. 2357-2359. Early in this treatment we read that its 'psychological genesis remains largely unexplained.' The new study does not change this."
The study draws a distinction between people who engage in homosexual acts and those who identified as "gay" or "homosexual," a distinction Miller noted was already central to the Church's teachings.
The Catechism teaches that homosexual acts are "intrinsically disordered" and "under no circumstances can they be approved." This is because, Miller said, only sexual acts oriented by their nature to the possibility of procreation and set within marriage are "compatible with the essential moral virtue of chastity and – as St. John Paul II emphasized in both his pre-papal and papal writings – love.".
"Any others are – independent of the subjective dispositions of those who take part in them – objectively hedonistic and selfish, rather than authentically loving. Obviously there are many types of sexual acts that could fall into this category - homosexual acts are by no means the only type."
Homosexual tendency or inclination, often called same-sex attraction, is defined by the Catechism as "objectively disordered," Miller said. This is because a desire which, if acted on, would lead to immoral acts is by its nature disordered, he said.
(Story continues below)
Subscribe to our daily newsletter
At Catholic News Agency, our team is committed to reporting the truth with courage, integrity, and fidelity to our faith. We provide news about the Church and the world, as seen through the teachings of the Catholic Church. When you subscribe to the CNA UPDATE, we'll send you a daily email with links to the news you need and, occasionally, breaking news.
As part of this free service you may receive occasional offers from us at EWTN News and EWTN. We won't rent or sell your information, and you can unsubscribe at any time.
But, Miller noted, the desire or inclination itself is not "morally wrong," since a person does not choose to have an inclination or exercise their free will over having it.
Central to understanding the distinction between sexual inclinations and acts, Miller said, is that all sexual acts are freely chosen; even if a person has an interior disposition toward engaging in homosexual acts, they have the same freedom to pursue them or not as a person inclined towards immoral acts with someone of the opposite sex.
"One can see that in this explanation of the Church's teaching, there is no reference of any sort to the cause of the homosexual tendency or disposition. This is simply irrelevant to the analysis of the moral goodness or evil of homosexual acts, and of the ordered or disordered character of the homosexual tendency or disposition."
Miller explained that the origin of a person's sexual orientation, whether biological, environmental, or experiential, had no bearing on what the Church teaches about the morality of acting on a particular sexual urge.
"These teachings do not depend on any assumption regarding the cause of the tendency or inclination," he said.
"Even if it could be shown that a homosexual tendency or orientation is wholly biologically determined, this would not affect at all the logic underlying the Church's teaching."