Linkage analysis in the spinal muscular atrophy type of facioscapulohumeral disease

Abstract

Facioscapulohumeral disease is probably a heterogeneous disorder. We have ascertained and sampled two multigeneration families with the neurogenic form of this disorder, considered to be a type of spinal muscular atrophy (FSHSMA). The two families have 36 affected members. Linkage studies with 10 expressed and seven DNA restriction fragment length polymorphism (RFLP) markers failed to show significant linkage (Zmax≥3-00). However, two areas of probable linkage were defined on chromosomes lp and 4q with the markers MNS (Z max=l-47 at Theta;max=0.10) and PGM1 (Zmax=0.94 at theta;max=0.001) respectively. We are using additional RFLPs from these and other areas of the human genome to screen these families for linkage to FSHSMA.