Svangerskap, Arv, Og Miljo (Pregnancy, Heredity and Environment)

This proposal describes a population-based case-control study of all Norwegian infants born with cleft lip or palate over a five-year period. The study will be jointly supported by the U.S. National Institute of Environmental Health Sciences (NIEHS), and the Norwegian National Institute of Public Health (SIFF) and Medical Birth Registry of Norway (MBR). Cases will be identified through the two surgery clinics that treat all clefts in Norway. Controls will be randomly selected from all live births through the MBR. Mothers will complete two selfadministered questionnaires; one regarding exposures before and during pregnancy, the other their diet during their early months of pregnancy. Biological specimens for DNA testing (blood samples, buccal swabs) will be collected from cases, controls and mothers in order to describe possible gene-environment interactions. With 750 cases and 1100 controls, this will be one of the largest and most complete field studies of facial clefting yet conducted.