Is television bad for your health? A birth cohort study in New Zealand (

), see also Comment, ibid: 226–7) suggests so. Nine hundred and eighty people followed up from birth were reassessed at age 26 years. The average duration of weeknight television watching between the ages of 5 and 15 years was positively correlated with current body mass index, poor fitness, cigarette smoking, and serum cholesterol, after adjustment for potential confounding factors. It was estimated that watching television for 2 hours or more a day during childhood accounted for 17% of overweight, 15% of raised serum cholesterol, 17% of smoking, and 15% of poor fitness at age 26.

Currently about 80% of children with acute lymphoblastic leukaemia (ALL) can be cured with chemotherapy but the causes of treatment failure are ill understood. Gene expression profiling may identify treatment resistant cases and point the way to even greater rates of success. Researchers in the Netherlands, the USA, and Germany (

, see also editorial, ibid: 601–3) used 14 500 probe sets to identify differentially expressed genes in leukaemia cells from 173 children with ALL. In vitro sensitivity to four drugs was first determined and gene expression profiling identified sets of genes that were expressed differently in cells sensitive or resistant to the drugs (prednisolone (33 genes), vincristine (40 genes), asparaginase (35 genes), …