Audrey Bonaventure

Genetic polymorphisms and childhood acute lymphoblastic leukemia: GWAS of the ESCALE study (SFCE)

Genetic polymorphisms and childhood acute lymphoblastic leukemia: GWAS of the ESCALE study (SFCE)

Triglycerides and risk of hemorrhagic stroke vs. ischemic vascular events: The Three-City Study.

BACKGROUND Few studies have assessed the relationship between triglycerides and the risk of hemorrhagic stroke, which contrasts the considerable number of studies about triglycerides and ischemic vascular events. We analyzed the association pattern between triglycerides and incident intracerebral hemorrhage as compared with coronary events and ischemic stroke, in a large cohort of elderly. METHODS Population-based, prospective cohort study among 8393 men and women participating in the Three-City Study, aged > or = 65 years at baseline. Fasting blood lipids, including triglycerides, were measured at baseline. Fatal and non-fatal strokes and coronary events were adjudicated and validated by scientific committees. Cox proportional hazards models were used to adjust for potential confounders. RESULTS During a mean follow-up of 5.0 years, 36 hemorrhagic strokes, 143 ischemic strokes, and 393 coronary events occurred. An increased level of triglycerides was associated with an increased risk of ischemic vascular events. Conversely, a low level of triglycerides (< or = 0.94 mmol/L) was associated with an increased risk of hemorrhagic stroke (adjusted hazard ratio 2.35; 95% confidence interval 1.18-4.70). The relationship with hemorrhagic stroke was mainly apparent in men, in individuals with high blood pressure, and in those with low levels of cholesterol. CONCLUSIONS In this large cohort of elderly men and women, low triglycerides levels were associated with an increased risk of hemorrhagic stroke and a decreased risk of ischemic vascular events. The association between triglycerides and hemorrhagic stroke was particularly strong in men, in subjects with high blood pressure and in those with low cholesterol levels.

ARID5B, IKZF1 and Non-Genetic Factors in the Etiology of Childhood Acute Lymphoblastic Leukemia: The ESCALE Study

Genome-wide association studies (GWAS) have identified that frequent polymorphisms in ARID5B and IKZF1, two genes involved in lymphoid differentiation, increase the risk of childhood acute lymphoblastic leukemia (ALL). These findings markedly modified the current field of research on the etiology of ALL. In this new context, the present exploratory study investigated the possible interactions between these at-risk alleles and the non-genetic suspected ALL risk factors that were of sufficient prevalence in the French ESCALE study: maternal use of home insecticides during pregnancy, preconception paternal smoking, and some proxies for early immune modulation, i.e. breastfeeding, history of common infections before age one year, and birth order. The analyses were based on 434 ALL cases and 442 controls of European origin, drawn from the nationwide population-based case-control study ESCALE. Information on non-genetic factors was obtained by standardized telephone interview. Interactions between rs10740055 in ARID5B or rs4132601 in IKZF1 and each of the suspected non-genetic factors were tested, with the SNPs coded as counts of minor alleles (trend variable). Statistical interactions were observed between rs4132601 and maternal insecticide use (p = 0.012), breastfeeding p = 0.017) and repeated early common infections (p = 0.0070), with allelic odds ratios (OR) which were only increased among the children not exposed to insecticides (OR = 1.8, 95%CI: 1.3, 2.4), those who had been breastfed (OR = 1.8, 95%CI: 1.3, 2.5) and those who had had repeated early common infections (OR = 2.4, 95%CI: 1.5, 3.8). The allelic ORs were close to one among children exposed to insecticides, who had not been breastfed and who had had no or few common infections. Repeated early common infections interacted with rs10740055 (p = 0.018) in the case-only design. Further studies are needed to evaluate whether these observations of a modification of the effect of the at-risk alleles by non-genetic factors are chance findings or reflect true underlying mechanisms.