Associated malformations in the family of a patient with Meckel syndrome: heterozygous expression?

Meckel syndrome is an inherited autosomal recessive disease. A family is described in which four persons had minor malformations related to the syndrome, suggesting the possibility of manifesting heterozygotes. It is uncertain whether these malformations represent partial expression of the disease or are coincidental. However, partial expression has been described in heterozygotes for other autosomal recessive diseases. Until the gene responsible for this lethal syndrome is cloned and sequenced, such relatives of the proband may be offered genetic counselling and prenatal diagnosis.