Biobanks and the importance of detailed phenotyping: a case study--the European Glaucoma Society GlaucoGENE project.

BACKGROUND: Dissecting complex diseases has become an attainable goal through large-scale collaborative projects under the term "biobanks." However, large sample size alone is no guarantee of a reliable genetic association study, and the genetic epidemiology of complex diseases still has many challenges to face. Among these, issues such as genotyping errors and population stratification have been previously highlighted. However, comparatively little attention has been given to accurate phenotyping. Study procedures of existing large-scale biobanks are usually restricted to very basic physical measurements and non-standardised phenotyping, based on routine medical records and health registry systems. DISCUSSION: Study procedures of existing large-scale biobanks are usually restricted. Considering that the objective of an association study is to establish genotype-phenotype correlations, it is doubtful how easily this could be achieved in the absence of accurate and reliable phenotype description. The use of non-specific or poorly defined phenotypes may partly explain the limited progress so far in glaucoma complex genetics. This report examines the European Glaucoma Society GlaucoGENE project, which is the only large multicentre glaucoma-specific biobank. Unlike previous biorepositories, this initiative focuses on detailed and standardised phenotyping and is expected to become a major resource for future studies on glaucoma.

Treatment of children with cystic fibrosis: central, local or both?

UNLABELLED: Owing to a lack of longitudinal studies, the effect of centralization of care on pulmonary function and survival remains unclear. Three different levels of involvement of centralized care in the treatment of paediatric cystic fibrosis patients were compared with regard to longitudinal pulmonary function and nutritional and microbiological status in a 3-y period, and the literature was reviewed on the possible advantages and disadvantages of centralized care. The study included 105 paediatric patients attending the Cystic Fibrosis Centre between January 1997 and January 2001. Twenty-three patients were treated by local paediatricians according to the protocol of the Centre and were seen only once a year at the Centre, for an annual check-up (local care). Forty-one patients were treated at the Centre only (centralized care). The remaining 41 patients were treated in close cooperation between the Centre and local hospitals, with patients visiting the doctors alternately (shared care). The mean annual changes in pulmonary function and body mass index from all patients, as well as a microbiological survey, were reviewed. No significant differences were found between the three groups for annual changes in FEV1, FVC and body mass index, nor did the review of microbial colonization show any significant differences between the groups. Because the groups in this study were relatively small, the results might have been influenced by lack of power. CONCLUSION: In this relatively small group, no differences in pulmonary function, nutritional status or microbiological colonization between the three levels of involvement of centralized care could be found. This could signify that local paediatricians have a special role in the care for patients with cystic fibrosis, in close cooperation with the specialists at the Centre.