FOK l Vitamin D Receptor Gene Polymorphism and Risk of Dental Caries: A Case-Control Study

Abstract

The prevalence of dental caries in individuals who practice good oral hygiene increasingly indicates that other etiological factors, such as genetic factors, may be responsible for occurrence of caries, and its prevalence in younger individuals, such as adolescents, is an early manifestation of their genetic makeup. Therefore, there is a need to investigate the correlation of various genetic factors with the occurrence of dental caries in populations. Thus, this study assessed the relationship between single nucleotide polymorphism (rs2228570) in the vitamin D receptor gene and dental caries susceptibility. After obtaining ethical approval (NU/CEC/2020/0339), 377 adults, aged 18–40 years, were included in this study. Among the participants consenting to participate, salivary samples were collected, and an oral examination was conducted using the World Health Care Oral Health Survey Format 2013. The DMFT and PUFA index scores were recorded along with basic demographic details. The subjects were categorized as caries-free (controls, DMFT = 0) and caries-active (cases). The case group was further divided into the high-risk group (DMFT ≤ 10), moderate-risk group (DMFT = 4–9), and low-risk group (DMFT = 1–3). Saliva samples were used for vitamin D level analysis and DNA isolation. Polymerase chain reaction-based restriction fragment length polymorphism analysis using Fok1 digestion was performed on the isolated DNA. Salivary vitamin D levels were markedly higher in the caries-free group than in the caries-active group ( $p<0.001$ ). The T allele of rs2228570 was significantly associated with having active caries, while the C allele was associated with being caries-free. Individuals with the rs2228570 TC genotype had 2.814-fold increased likelihood, and individuals with the TT genotype had 3.116- fold increased likelihood of being caries-active. This finding is important in terms of patient counselling, as well as possibly in terms of prevention and treatment of caries.