[Genetic and biochemical studies on familial neuroblastoma].

The diagnosis of bilateral neuroblastoma in the adrenal glands in a newborn led to the discovery of a family with clustering of tumors of neural crest origin. According to the two-mutation model of neuroblastoma development we searched for individuals with the first mutation, who are predisposed to neuroblastoma. Neither chromosomal analysis of the peripheral blood nor the examination of catecholamines nor of gm-phenotypes could mark the first step to neuroblastoma. However, it was possible to detect cystationinuria in familial neuroblastoma for the first time. Cystationinuria could be calssified as secondary to vitamin B6-deficiency. Since cystathioninuria and vitamin B6-deficiency were not only seen in blood-relations but also in relatives by marriage there was no fixed correlation to individuals with tumor or their relatives.