Familial precocious puberty is rare. To date, less than 20 kindreds have been described.1-5 This form of precocious puberty occurs almost exclusively in boys and may involve several generations.1-3 The disorder may be inherited as a sex-limited autosomal dominant trait transmitted only through affected males1 or through affected males or unaffected parents.2 Less commonly, it may be X-linked, transmitted only through unaffected females.3 To date, only two incidences of familial sexual precocity have been mentioned in the literature where the condition had appeared in siblings of the opposite sex.4,5 We report a family in which idiopathic precocious puberty occurred in a brother, sister, and in their father.
Report of Cases.—Case 1.—A 7-year 8-month-old girl was seen for evaluation of early puberty. She had been the 3,400-g product of an uncomplicated term pregnancy and delivery. Early psychomotor development was normal. Until age 5,
HOPWOOD NJ, KELCH RP, HELDER LJ. Familial Precocious Puberty in a Brother and Sister. Am J Dis Child. 1981;135(1):78–79. doi:10.1001/archpedi.1981.02130250064020