Association Analysis of Polymorphisms in BIN1 , MC1R , STARD6 and PVRL2 with Mild Cognitive Impairment in Elderly Carrying APOE ϵ4 Allele

Background Apolipoprotein (APOE) e4 is recognized as an independent risk factor for mild cognitive impairment (MCI). However, not everyone with the e4 allele develops MCI, suggesting that other susceptibility genes exist. This study aimed to identify MCI susceptibility genes, including BIN1, MC1R, STARD6, and PVRL2, in elderly Han Chinese and to verify their association with APOE e4 allele in MCI onset. Methods To determine whether polymorphisms in BIN1 (rs6733839, rs7561528), MC1R (rs2228479), STARD6 (rs10164112), and PVRL2 (rs6859) occurred in elderly MCI patients carrying APOE e4 allele, we carried out a case-control study including 285 MCI patients and 326 healthy controls. Results Statistically significant differences in the proportion of APOE e4 carriers, and BESCI, ADAS-cog, and CNT scores existed between the NC and MCI groups (all P 0.05). When stratified by APOE e4 status (carriers/non-carriers), genotype frequencies of BIN1 rs7561528, STARD6 rs10164112, and PVRL2 rs6859 among the four groups (NCe4+, NCe4-, MCIe4+, MCIe4-) were significantly different. Additionally, our results suggest a significant association between MCI and BIN1 rs7561528, STARD6 rs10164112, and PVRL2 rs6859 (all P<0.05) in elderly carriers. Conclusion This suggests that among the Han Chinese, MCI in elderly APOE e4 carriers may be related to the BIN1 (rs7561528), STARD6 (rs10164112) and PVRL2 (rs6859). Genotype AA of rs7561528 and TT of rs10164112 might be protective factors against MCI in elderly APOE e4 carriers.