A linkage analysis with chromosome 9 markers was performed in 33 families with Friedreich ataxia (FA). Linkage with D9S15, previously established by S. Chamberlain et al. (1988, Nature London 334:248-249) was confirmed in our sample (z(theta) = 6.82 at theta = 0.02) while INFB (interferon-beta gene) shows looser linkage. An additional marker, D9S5, was also shown to be closely linked to FA (z(theta) = 5.77 at theta = 0.00).