Consanguinity, or marriage between biologically related individuals, can increase the likelihood of both partners carrying the same rare genetic variant, raising the risk of hereditary disorders and congenital conditions in their children. Understanding consanguineous marriage requires attention to more than its genetic implications. Family ties, financial considerations, and cultural attitudes toward marriage all play a role.

A new LAU-led study set out to examine the prevalence of consanguinity in Lebanon and the knowledge, attitudes, and social factors surrounding it to help inform genetic counseling and public-health programs.

The research was conducted by faculty from the Department of Human Genetics at the Gilbert and Rose-Marie Chagoury School of Medicine: Dr. Eliane Chouery, professor and genetics discipline co-coordinator; Dr. Cybel Mehawej, associate professor and genetics discipline co-coordinator; and Dr. André Megarbane, assistant dean for research and department chair; along with Dr. José-Noel Ibrahim, associate professor of biology at the School of Arts and Sciences.

In the study, “Consanguinity in the Lebanese population: knowledge, attitudes and practices,” published in the Journal of Community Genetics, the researchers used an anonymous online questionnaire that included 984 Lebanese adults aged 18 to 65. The survey measured parental consanguinity, knowledge of genetic implications and premarital screening, and attitudes toward consanguineous marriage and genetic counseling. 

Conducting the study involved several notable hurdles. Achieving a large, geographically diverse sample meant that individual face-to-face interviews were not feasible, prompting the team to rely primarily on online platforms such as email, WhatsApp, and social media, explained Dr. Chouery. This approach “may have introduced sampling bias, as it may have disproportionately recruited younger, more educated, and digitally active individuals,” she noted, while also limiting participation among those with restricted internet access or lower digital literacy. It also restricted the researchers’ ability to reach participants from rural villages and more remote areas where consanguineous marriages are reported to be higher, potentially underrepresenting populations with different viewpoints and practices.

Another major challenge was the cultural sensitivity of the topic, noted Dr. Mehawej. Given that consanguinity is closely associated with Lebanese family traditions, religious beliefs, and cultural values, “participants may have been hesitant to disclose personal or family-related information or may have provided socially desirable responses rather than reporting their true attitudes and practices,” she said.

The survey showed that family background shaped attitudes toward the practice. Respondents whose parents were related were more likely to consider marriage between relatives acceptable and understandable. They were also more likely to believe it strengthened family bonds, with around 16 percent agreeing compared with 7 percent of those whose parents were unrelated. Nevertheless, most respondents rejected the idea that it strengthened family bonds or preserved family wealth.

Furthermore, the statistical model found that the place of residence was independently associated with consanguinity rates. The practice was most prevalent among respondents from the Bekaa, followed by those from South Lebanon and North Lebanon, respectively. By contrast, Beirut and Mount Lebanon had the lowest prevalence.

Knowledge of the genetic implications varied. The median knowledge score was eight out of 13, while around 60 percent were classified as having poorer knowledge. Women, graduate-degree holders, students, full-time workers, and people aged 21 to 25 had significantly higher adjusted odds of good knowledge. Less than half were classified as holding a positive attitude toward consanguinity. Insufficient income, having related parents, and poorer knowledge predicted a more favorable view, while students were less likely to hold one.

The findings support public-health efforts that combine clear information about genetic risks with attention to families’ views and circumstances. Screening and counseling should provide space for people to discuss family expectations, financial concerns, and their understanding of related marriage, while supporting informed decisions without stigmatizing families.

Tailoring education and counseling to communities with different patterns of prevalence, knowledge, and attitudes may also prove more useful than a single approach applied nationwide.

Highlighting the clinical urgency that underpins these educational and counseling efforts, Dr. Megarbane noted that autosomal recessive (AR) disorders contribute substantially to pediatric morbidity and mortality, particularly in populations with high rates of consanguinity. Their clinical presentation and severity range widely, from mild conditions to severe, life-threatening disorders presenting in infancy or childhood. Globally, prevalent and clinically important AR disorders include cystic fibrosis, sickle cell disease, spinal muscular atrophy, phenylketonuria, and congenital adrenal hyperplasia.

However, Lebanon’s genetic profile is distinctive. “In Lebanon and other populations with high rates of consanguinity, the spectrum and relative prevalence of AR disorders may differ from those observed globally,” explained Dr. Megarbane. He pointed out that β-thalassemia, α-thalassemia, familial Mediterranean fever, and numerous rare developmental and neurogenetic disorders are especially relevant locally due to population structure, founder effects, and consanguinity.

This clinical landscape makes timely detection and modern screening all the more crucial, according to Dr. Ibrahim. “Importantly, therapeutic advances have made effective treatments available for some previously untreatable AR disorders, particularly when diagnosis is made early,” he stated.

This progress reinforces the need to raise awareness, implement appropriate screening strategies, and ensure early diagnosis, as timely identification can significantly improve clinical outcomes and, in some cases, alter the natural history of the disease.

To browse more scholarly output by the LAU community, visit our open-access digital archive, the Lebanese American University Repository (LAUR).