Gene-environment interaction in molar-incisor hypomineralization.

Area of Science:

• Dentistry
• Genetics
• Pediatrics

Background:

• Molar incisor hypomineralization (MIH) is a dental enamel defect affecting permanent molars and incisors, characterized by white to brown lesions and rapid caries.
• The etiology of MIH is multifactorial, with suspected genetic and environmental influences, but definitive risk factors remain unclear.
• Genes such as IRF6 and TGFA are crucial during craniofacial development, suggesting a potential role in MIH predisposition.

Purpose of the Study:

• To investigate the potential interaction between IRF6 and TGFA genes in the predisposition to MIH.
• To explore the association between environmental factors (respiratory issues, malnutrition, infections, medication intake) and MIH development in children aged three and older.

Main Methods:

• Salivary DNA was extracted from 1,065 individuals across four cohorts.
• Genotyping was performed for nine single nucleotide polymorphisms (SNPs) related to IRF6 and TGFA.
• Association tests and logistic regression analyses were conducted using PLINK software.

Main Results:

• A significant interaction between TGFA rs930655 and other markers was identified in the Turkish cohort, but not in others.
• A statistically significant association (p<0.05) was found between MIH and medication intake after the age of three.
• These findings suggest a potential link between early childhood environmental exposures and MIH development.

Conclusions:

• Genetic interactions involving TGFA may contribute to MIH susceptibility in specific populations.
• Environmental factors, particularly medication use acquired during early socialization, appear to play a role in the etiology of MIH.
• Further research is warranted to elucidate the complex interplay of genetic and environmental factors in MIH.