Impact of consanguinity on dental and craniofacial genetic disorders: a systematic review

Dental and craniofacial anomalies are a complex developmental disorder and are related to genetic and environmental causes. Consanguinity and endogamy increase the risk of autosomal recessive conditions through increased homozygosity and decreased genetic diversity, thus increasing the prevalence and severity of craniofacial and dental anomalies. To evaluate the impact of consanguinity and endogamy on the prevalence, severity, and genetic transmission of dental and craniofacial disorders in human populations. Using guidelines outlined in PRISMA, thorough search of PubMed, Scopus, Web of Science, EBSCO, LILACS and Cochrane databases was done up to April 2026. Observational studies reporting dental or craniofacial anomalies in consanguineous or endogamous populations were included. Two reviewers screened, extracted data and assessed risk of bias independently and GRADE was used to grade the certainty of evidence. Of 639 records, 14 studies met eligibility criteria and included cross-sectional, cohort and case-control study designs from a range of geographic regions. A significant correlation was observed in the prevalence of anomalies with consanguinity (dominantly first cousin marriages), both of which were found to have high prevalence of anomalies including cleft lip/palate, hypodontia, microdontia, taurodontism and supernumerary teeth. There was higher severity and family history. Majority of findings were consistent with genetic basis. However, heterogeneity in study design and confounding factors limited the ability to draw firm conclusions. There is evidence that consanguinity are frequently associated with dental and craniofacial anomalies, but the evidence varies in strength among populations. Evidence relating specifically to endogamy was limited. These findings emphasize the importance of early diagnosis, genetic counselling and public health interventions in high-risk groups, and highlight the need for standardized genetically informed future research.