ESPE Abstracts

Background: The age of onset of puberty is known to be influenced by poorly understood genetic and environmental factors. Familial forms of precocious puberty suggest the involvement of autosomal genetic factors.

Objective and hypotheses: We evaluated the mode of inheritance of precocious puberty in a large series of familial cases of both central precocious puberty (CPP) and advanced puberty.

Method: A retrospective, single-centre study was carried out on 154 children, of whom 93 had CPP and 61 had advanced puberty, and all had an affected 1st, 2nd and/or 3rd degree relative.

Results: 125 cases (81%, 91 girls and 34 boys) had at least one affected 1st degree relative. 29 cases (19%, 25 girls and four boys) had only 2nd (n=18) or 3rd (n=3) or both (n=6) degree relatives affected. The analysis of informative pedigrees showed a penetrance of 33%. Interestingly, 88 cases exhibited unilineal inheritance of which 86 cases were matrilineal.

Conclusion: The data confirm the high incidence of affected girls with precocious puberty compared with boys. The mode of inheritance of the phenotype is predominantly matrilineal suggesting a possible imprinting anomaly as the underlying aetiology of the phenotype.