A preliminary examination of the effects of genetic variants of redox enzymes on susceptibility to oedematous malnutrition and on percentage cytotoxicity in response to oxidative stressin vitro

Abstract

Variation in this small set of genes seems unlikely to have a large impact on either risk of OM or cytotoxicity after H(2)O(2) exposure. The use of larger sample sizes to test the effects of a much larger set of genetic variants will be required in order to determine whether genetic variation contributes to the risk of OM. Such studies have potential for improving our understanding of causal pathways in OM.

A cross‐sectional clinic‐based study exploring whether variants within the glutathione S‐transferase, haptoglobin and uridine 5′‐diphospho‐glucuronosyltransferase 1A1 genes are associated with interindividual phenotypic variation in sickle cell anaemia in Jamaica

“…Moreover, the potential impact of GST gene variants on susceptibility to several human diseases has also been studied . For instance, it has been postulated that the relative importance of G S T enzymes to endogenous antioxidant defence might be heightened in conditions, such as severe acute malnutrition, where the protection against oxidative stress that can usually be provided by other important enzymes (eg catalase and superoxide dismutase) might be compromised . In the current study, multivariable regression yielded statistically significant negative associations between the HbF, MCH and reticulocyte phenotypic measures and the GSTP1 105 Ile/Val heterozygote, but none between any of these phenotypes and either GSTP1 105 Ile/Ile or GSTP1 105 Val/Val homozygotes.…”

“…20 For instance, it has been postulated that the relative importance of GST enzymes to endogenous antioxidant defence might be heightened in conditions, such as severe acute malnutrition, 21,22 where the protection against oxidative stress that can usually be provided by other important enzymes (eg catalase and superoxide dismutase) might be compromised. 23 In the current study, multivariable regres- 24 calling for further scrutiny of this purported phenomenon in future studies.…”

“…For many phenotypic outcomes, the role of genetic factors is either small in an absolute sense or is small relative to environmental factors. 23 Hence, the influence of single genetic factors on such outcomes in HbSS was not uncovered here because the current exploratory study might have lacked sufficient statistical power to disclose the small but potentially important influence of these particular polymorphisms on interindividual phenotypic variation. Nevertheless, the estimates that this study has generated are now available to inform the design of further studies that can potentially test for these and other genotype-phenotype relationships by deploying larger participant samples and broader panels of genes.…”

A Cross-sectional Clinic-based Study Exploring whether Variants within Genes Coding for Enzymes of the Transmethylation and Trans-sulphuration Pathways Are Associated with Inter-individual Phenotypic Variation in Sickle Cell Anaemia in Jamaica

“…It could be argued, though, that the relatively small number of significant associations obtained in this study was not particularly surprising. For many phenotypic outcomes, the role of genetic factors is small either in an absolute sense or relative to environmental factors (18). Hence, the influence of single genetic factors on such outcomes in HbSS might not have been uncovered here because the current exploratory study lacked sufficient statistical power to disclose the small but potentially important influence of these particular polymorphisms on inter-individual phenotypic variation.…”

Exploring Antioxidants

“…Antioxidant centred epidemiological studies encompass survey, case-control and longitudinal follow-up designs. Epidemiological studies can be used to establish a relationship between a proposed antioxidant and a particular disease condition and can also facilitate an estimate of the magnitude of any observed relationship (6,7). Despite their unique strengths though, epidemiological approaches do not, by themselves, definitively establish causal relationships between a postulated antioxidant and a disease condition.…”