LONG-TERM FOLLOW-UP OF 2 SIBS WITH LARSEN SYNDROME POSSIBLY DUE TO PARENTAL GERM-LINE MOSAICISM

Larsen syndrome is a heterogeneous (autosomal dominant or recessive) d isorder of characteristic facial changes, multiple joint dislocations, and bone deformities. Few data on the adult presentation of the reces sive form of this disorder have been reported; thus, we set out to des cribe two sibs thought to be affected with autosomal recessive Larsen syndrome who were evaluated as infants and later as adults. Aside from secondary joint changes and the presence of cataracts, changes descri bed in children with autosomal recessive Larsen syndrome were noted. T hree years after evaluation, the sister gave birth to a daughter with Larsen syndrome. This occurrence raises the possibility of germ-line m osaicism as the mode of inheritance in this family. Thus, germ-line mo saicism must be considered in the genetic counseling of families with Larsen syndrome in which neither parent appears affected. These patien ts also illustrate that despite the severe skeletal and joint deformit ies, the prognosis can be good with careful orthopedic management. (C) 1993 Wiley-Liss, Inc.