Association between polymorphisms in ABO gene and stroke patients with small artery occlusion in southern Chinese Han population.

• First to study ABO gene polymorphisms associated with small artery occlusion stroke. • rs532436 is associated with small artery occlusion stroke in Chinese Han population. • rs532436 heterozygous genotype increases the risk of small artery occlusion stroke. The purpose of this study was to investigate associations between two single nucleotide polymorphisms (SNPs) rs505922 and rs532436 in ABO gene and the risk of small artery occlusion stroke (SAO) in southern Chinese Han population. Our case-control study comprising 121 patients with SAO and 136 controls. All participants were Han population of southern China. IS sub-type was defined on the basis of the TOAST criteria. SAO was strictly diagnosed after a systematic physical examination and neuroimaging via MRI. Genotype analysis was conducted by the snapshot technique. The distribution of rs532436 genotype between these two groups showed a statistically significant difference (P = 0.048) while that of rs505922 genotype showed no significant difference (P = 0.572). SNP rs532436 was significantly associated with SAO in overdominant model (GA vs. GG + AA) after adjusting for age, hypertension history, diabetes history and cigarette smoking (adjusted OR = 2.03, 95% CI: 1.14–3.62, P = 0.016). However, under all genetic models, the rs505922 polymorphism failed to show association with SAO. The results indicate that rs532436 polymorphism in ABO gene may have association with SAO in southern Chinese Han population. [ABSTRACT FROM AUTHOR]