ABSTRACT
@#Genetic studies have reported the association between polymorphism in MYO1H with mandibular prognathism. MYO1H is found in skeletal muscle sarcomeres and is expressed in the mandibular jaw cartilage signifying its importance during craniofacial development. This study aimed to characterise the genotype and allele of MYO1H single nucleotide polymorphism (SNP) (rs3825393) and to associate the SNP with mandibular prognathism in Class III skeletal malocclusion. This was a casecontrol study, which involved 57 Malay subjects with 30 Class I (control) and 27 Class III skeletal base patients (case). Cephalometric measurements were taken prior to collection of saliva samples. MYO1H SNP (rs3825383) was genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Chi-square (χ2 ) test was used to compare genotype and allele frequencies between the groups while Hardy-Weinberg Equilibrium (HWE) was applied to assess distribution of genotype frequency in both classes. MYO1H SNP (rs3825393) did not yield significant association with mandibular prognathism with p = 0.33; OR = 0.66; 95% CI = 0.289~1.518, that was reflected by no significant difference in allele (p > 0.05) and genotype (p > 0.05) frequency between control and study group. Nevertheless, AA genotype depicted the highest frequency in both groups. The genotype distribution in both groups was in concordance with HWE (p > 0.05). Our data showed no association of MYO1H SNP (rs3825393) with mandibular prognathism. Interestingly, we observed Allele A representing the major allele in Malay population. Presence of MYO1H SNP (rs3825393) was detected in samples analysed. Larger number of samples is required to confirm the involvement of MYO1H polymorphisms in mandibular prognathism.