A genetic linkage study in 15 families of individuals with von Recklinghausen neurofibromatosis.

A linkage analysis between the gene for von Recklinghausen neurofibromatosis (NF) and 21 genetic markers was carried out using the computer program LIPED. The study group included 15 families composed of 84 individuals, 51 of whom were affected with NF; there were six three-generation families and nine two-generation families. Lod scores excluded tight linkage (Z less than -2.0) between eight genetic markers and NF and were inconclusive for nine markers. Four markers were not informative. The analysis failed to confirm either the previously suggested linkage between NF and the plasma vitamin D-binding protein Gc or the possibility of linkage of NF to the secretor locus suggested by reports of two families segregating for NF and myotonic dystrophy.