Association of DRD4 promoter-associated methylation with mild cognitive impairment in Han and Uygur populations

Purpose Mild cognitive impairment (MCI), the symptomatic pre-dementia phase of Alzheimer’s disease, is characterized by objective or subjective memory impairment without affecting daily activity. Dopamine receptors play a pivotal role in the modulation of memory and cognitive functions. Our study focused on the association between DRD4 methylation and MCI in Uygur and Han populations. Patients and methods: Methylation was measured using bisulfite pyrosequencing. Results Our results indicated that MCI-related hypermethylation was detected in the Uygur (CpG 1) and Han (CpG 1–3) populations, and subgroup analyses by sex in the Uygur population indicated consistent results, while in the Han subgroup, DRD4 hypermethylation was only observed in the male group. Ethnic differences in CpG 4(CpG: Cytosine Phosphate Guanine)in male cases, CpG 1 in overall control and CpG 3 in male controls. Regional distinctions were shown between CpG 1 and CpG 4 in the male subgroup. Diverse correlations were observed. CpG 1 methylation in the Uygur male control, Uygur female case, and Han female control groups was significantly correlated with age, Glu, and HDL-C, respectively. CpG 2 in Uygur male controls and Uygur female patients showed correlations with Glu and TG levels. CpG 3 in Uygur male and Han male controls was significantly correlated with TC and HDL-C levels. CpG 4 in Uygur female controls and Han female patients correlated with Glu and age. Conclusion Our findings provide novel insights into DRD4 methylation in Uygur and Han populations.