Prevalence of glutathione S-transferase gene deletions and their effect on sickle cell patients.

Background: Glutathione S-transferase gene deletions are known detoxification agents and cause oxidative damage. Due to the different pathophysiology of anemia in thalassemia and sickle cell disease, there are significant differences in the pathophysiology of iron overload and iron-related complications in these disorders.

Objective: The aim of this study was to estimate the frequency of the GSTM1 and GSTT1 genotypes in sickle cell disease patients and their effect on iron status.

Breastfeeding as a time-varying-time-dependent factor for birth spacing: multivariate models with validations and predictions.

Data used in the present study are from the National Family Health Survey (NFHS-I) 1992-93 (International Institute for Population Sciences 1995), India. Our study has developed Cox model analyses to see the effect of breastfeeding as a time-varying and time-dependent factor on birth spacing. While it is acknowledged that breastfeeding has a protective effect on birth spacing, such analysis of breastfeeding allows for a more nuanced understanding of that effect.