CLINICAL AND MOLECULAR STUDIES IN A LARGE DUTCH FAMILY WITH NOONAN SYNDROME

We describe the largest Noonan syndrome (NS) family reported to date. The manifestations of the affected relatives are discussed. In the abs ence of a biochemical marker NS is still a clinical diagnosis. The dia gnostic criteria that were used are presented compared with ether publ ished criteria for diagnosing NS. The large size of this family enable d us to test the possible involvement of candidate regions by multipoi nt linkage analysis. Both the region surrounding the NF1 locus on chro mosome 17 and the proximal part of chromosome 22 could be excluded. Si nce NS may well be heterogeneous, the use of such a large family in li nkage studies of NS should prove indispensable. (C) 1994 Wiley-Liss, I nc.