Oxygen free radical scavenger enzyme polymorphisms in systemic sclerosis

We performed a case-control study of polymorphisms of glutathione S-transferase (GST) isoenzymes and manganese superoxide dismutase (MnSOD) in black South Africans with systemic sclerosis (SSc). The frequency of the GSTM1*B phenotype was significantly decreased in the overall SSc group compared with controls (OR = 0.19, pcorr < .05), implying a possible protective effect against development of the disease. There was also a trend toward increased MnSODAla allele and phenotype frequencies in the diffuse cutaneous SSc subset compared with controls (OR = 2.11 and 3.15, respectively, pcorr < . 1). Our findings provide new data on the distribution of GST and MnSOD polymorphisms in healthy Africans and further evidence that genetic factors may have a contributory role to play in predisposing to oxidative stress in SSc. (C) 2004 Elsevier Inc. All rights reserved.