[The interaction of biological and social factors on the effect of treatment in cases of phenylketonuria (author's transl)].

The dietary control was poor in 14, good in 21, and excellent in 6 out of 41 patients with pku which had been treated early. The mean IQ at termination of the diet in these groups was 80 +/- 17, 94 +/- 11, and 93 +/- 8 resp. In the group of the children with poor dietary control, it was ascertained that, in comparison to the groups with good and excellent control; the parents education at school had been mainly terminated with a lower grade, none of the parents had been to college, the mothers were often without any professional training, knowledge of genetical problems was poor, the parents had been somewhat older at the birth of the child and the mean number of children per family was higher.