The present paper is concerned with a report on a kin affected with Pelger-Huet's anomaly (PHA). 17 living heterozygous carriers of the anomaly are covered by the pedigree. Three further dead carriers of anomaly could be detected by genealogical studies. Polydactylia was found in three members of the kin, viz. in two sisters and a niece of second degree. Polydactylia could be found to have occurred at the same place in all these three persons concerned, with only one of them being a carrier of PHA: in all cases it was the doubling of the fifth toe of the right leg. This localisation of the same kind favours the assumption that this malformation is caused by genetics, however, without its having any genetical connection with PHA. The hypothesis was put forth that an enzyme defect is responsible for this hyposegmentation which simultaneously could have an impact on further elements of the mesenchymal tissue playing an important part in the histogenetic differentiation of organs.

Polydactyly in the Pelger-Huet anomaly