[Contribution to information and genetic counseling in Mekkel's syndrome (author's transl)].

The deformity syndrome nowadays named after Meckel is characterized by the following principal features: occipital encephalocele, cystic kidneys and a polydactyly. According to the available findings in twins and families, an autosomal recessive lethal syndrome is involved. In 8 (= 16.6%) of 48 families, the parents of the feature carrier were blood relations. Heterozygous anlage carriers cannot yet be recognized as such. To make a statement in genetic counselling today, ultrasonic diagnosis and an amniocentesis must be carried out early in a pregnancy at risk.